Question No. 1 Marks = = 5 +5 +2 = 12
The driver of a 2.0 × 103 kg red car traveling on the highway at 45m/s slams on his brakes to avoid striking a second yellow car in front of him, which had come to rest because of blocking ahead as shown in above Fig. After the brakes are applied, a constant friction force of 7.5 × 103 N acts on the car. Ignore air resistance.
(a) Determine the least distance should the brakes be applied to avoid a collision with the other vehicle?
(b) If the distance between the vehicles is initially only 40.0 m, at what speed would the collision occur?
(c) Write your conclusive observations on the result obtained from this numerical. i.e. the importance of Physics in daily life.
Question No. 2 Marks = 8
Consider an automobile moving at v mph that skids d feet after its brakes lock. Calculate how far it would skid if it was moving at 2v and the brakes were locked.
Answers
The kinematics and Newton's second law we can find the results for the questions about the braking movement of the car are;
Question 1.
a) The stopping distance is: x = 270 m
b) The initial velocity is: v₀ = 17.3 m / s
c) Concepts of kinematics and Newton's second law show us the expressions to make safe trips and avoid accidents on the roads.
Question 2.
The stopping distance is: x = 4d
Given parameters
Mass of the red carriage m1 = 2,0 10³ kg Red car speed vo = 45 m / s Friction force fr = 7.5 10³ N.To find
Question 1.
a) Minimum braking distance.
b) If the distance is x = 40.0 m, what speed should the vehicles have?
c) Conclusive importance of physics in daily life.
Question 2.
The distace to stop.
Kinematics studies the movement of bodies, looking for relationships between the position, speed and acceleration of bodies.
v² = v₀² - a2 x
Where v and v₀ are the current and initial velocity, respectively, at acceleration and x the distance traveled.
Newton's second law states that the net force is proportional to the mass and the acceleration of the body.
F = ma
Where F is force, m is mass and acceleration.
In the attachment we see a diagram of the forces in the system. Let's look for the acceleration of the body
fr = m a
a =[tex]\frac{fr}{m}[/tex]
a = [tex]\frac{7.5 \ 10^3}{2.0 \ 10^3 }[/tex]
a = 3.75 m / s²
This acceleration is in the opposite direction to the speed.
Let's find the distance needed to stop, the final speed is zero.
0 = v₀² - 2 ax
x = [tex]\frac{v_o^2 }{ 2a}[/tex]
Let's calculate.
x = [tex]\frac{45^2 }{2 3.75}[/tex]
x = 270 m
This is the minimum distance that the two vehicles must separate to avoid a collision.
b) We look for speed.
v₀ = [tex]\sqrt{2ax}[/tex]
v₀ = [tex]\sqrt{2 \ 3.75 \ 40.0}[/tex]
v₀ = 17.3 m / s
c) The concepts of kinematics and Newton's second law show us the expressions to make safe trips and avoid accidents on the roads.
2) They indicate that the initial velocity is v and the distance traveled to stop is d, let's find the acceleration.
0 = v₀² - 2ax
Let's substitute.
a = [tex]\frac{v^2}{2d}[/tex]
They ask the distance traveled if this car traveled from an initial speed 2v.
0 = v² - 2 a x
x = [tex]\frac{v^2}{2a}[/tex]
We substitute
x = [tex]\frac{(2v)^2 }{2} \ (\frac{2d}{v^2})[/tex]
x = 4 d
In conclusion, using the kinematic relations and Newton's second law we can find the results for the questions about the braking movement of the car are;
Question 1
a) The stopping distance is: x = 270 m
b) The initial velocity is: v₀ = 17.3 m / s
c) concepts of kinematics and Newton's second law show us the expressions to make safe trips and avoid accidents on the roads.
Question 2.
The stopping distance is x = 4d
Learn more about kinematics here: brainly.com/question/13202578
Related Questions
Define the term dimension
Answers
Answer:
Q1. A measurable extent of a particular kind, such as length, breadth, depth, or height.
Q2. A dimensional constant is a physical quantity that has dimensions and has a fixed value. Some of the examples of the dimensional constant are Planck's constant, gravitational constant, and so on.
Q3. Physical quantities which posses dimensions and have variable are called dimensional variables. Examples are length, velocity, and acceleration etc.
Q4. Dimensionless variables are the quantities which doesn't have any dimensions the the value is a variable. Eg: angle = arc/ radius. Dimensions = L/L. = 1. So angle does not have any dimensions and the value can vary.
Q5. Principle of Homogeneity states that dimensions of each of the terms of a dimensional equation on both sides should be the same. This principle is helpful because it helps us convert the units from one form to another.
Q6. Dimensional analysis has been around a long time, Newton called it the "Great principle of Similitude", but the modern form can be traced back to James Clerk Maxwell. It was Maxwell who distinguished mass [A/], length [£], and time [7"] as the independent dimensions from which others could be derived.
Q7. Mass, length, time, temperature, electric current, amount of light, and amount of matter.
Q8. Dimensional analysis is used to convert the value of a physical quantity from one system of units to another system of units. Dimensional analysis is used to represent the nature of physical quantity. The expressions of dimensions can be manipulated as algebraic quantities.
Hope that helps. x
What is the acceleration due to gravity in a region where a simple pendulum having a length 75.000 cm has a period of 1.7357 s?
Answers
Answer:
Explanation:
T = 2π[tex]\sqrt{L/g}[/tex]
(T / 2π)² = L/g
g = 4π²L/T²
g = 4π²(0.75000)/(1.7357)²
g = 9.82814766...
g = 9.8281 m/s²
A 70 kg hunter, standing on frictionless ice, shoots a 42 g bullet horizontally at a speed of 650 m/s . Part A What is the recoil speed of the hunter
Answers
Answer:
Explanation:
momentum is conserved. Initial momentum was zero, so final total momentum must also be zero
0.042(650) + 70v = 0
v = -0.39 m/s
|v| = 0.39 m/s
Calculate the change in the kinetic energy (KE) of the bottle when the mass is increased. Use the formula
KE = one half.mv2, where m is the mass and v is the speed (velocity). Assume that the speed of the soda bottle falling from a height of
0.8 m will be 4 m/s, and use this speed for each calculation.
Record your calculations in Table A of your Student Guide.
When the mass of the bottle is 0.125 kg, the KE is
✔ 1
kg m2/s2.
When the mass of the bottle is 0.250 kg, the KE is
✔ 2
kg m2/s2.
When the mass of the bottle is 0.375 kg, the KE is
✔ 3
kg m2/s2.
When the mass of the bottle is 0.500 kg, the KE is
✔ 4
kg m2/s2.
Answer included in Question
Answers
Answer:
kinetic energy is given as KE = (0.5) m v²given that : v = speed of the bottle in each case = 4 m/s when m = 0.125 kg KE = (0.5) m v² = (0.5) (0.125) (4)²
Explanation:
Answer:
1. 0.5 2. 2 3. 3.75 4. 5
Explanation:
2. An object is falling under gravity with terminal velocity. What is happening to its speed?
A. It is decreasing to a lower value.
B. It is increasing
C. It is decreasing to zero.
D. It is staying constant.
Answers
Answer:
the speed of the object has become constant.
Explanation:
At terminal velocity, air resistance equals in magnitude the weight of the falling object. Because the two are oppositely directed forces, the total force on the object is zero, and the speed of the object has become constant.
Four balls with different masses are dropped from the heights shown. Air resistance may be ignored. Which ball has the greatest average speed?
Answers
Answer:
The one falling from the greatest height will have the greatest speed.
h = 1/2 g t^2 time for ball to fall distance h
h2 / h1 = t2^2 / t1^2 dividing equations
h2 / t2^2 = h1 / t1^2
Let v be the average speed (v2 = h2 / t2)
1 / t2 * v2 = 1 / t1 * v1
v2 / v1 = t2 / t1 the one taking the longest to fall has the greater av. speed
Check:
h4 / h1 = t4^2 / t1^2 or
t4 / t1 = (h4 / h1)^1/2
In this case t4 / t1 = (4 / 1)^1/2 = 2 or twice the average speed
t1 = (2 h / g)^1/2 = .2^1/2 = .447 using g = 10
t4 = (2 h / g)^1/2 = .8^1/2 = .894
v1 = 1 / .447 = 2.24 m/s average speed
v4 = 4 / .894 = 4.47 or twice the average speed
8 N to the left , and 4 N to the right. Find the net force. Is this balanced?
Answers
Explanation:
12N by first law of newton is net force after colloision
Which statement best describes wavelength?
wavelength is the speed at which a wave travels
wavelength is the height vertically of a wave
wavelength is the length of wave per sec
wavelength is the horizontal length of one complete wave cycle
Answers
Answer:
B
Explanation:
Wave length is the height perpendicular verically of a wave
Answer:
b
Explanation:
makes the most sense to me
2 difference between calorimetry and calorimeter
Answers
Calorimetry :
the process of measuring the amount of heat released or absorbed during a chemical reaction.
Calorimeter :
device for measuring the heat developed during a mechanical, electrical, or chemical reaction, and for calculating the heat capacity of materials.
Which of the following is an incorrect statement?
The pulley is a special type of wheel and axle.
The mechanical advantage of a pulley with three ropes is one.
The mechanical advantage of a block and tackle pulley with two pulleys is two.
The mechanical advantage of a fixed pulley is one.
PLZ HELP WILL MARK BRAINLIEST
Answers
Answer:
Explanation:
The mechanical advantage of a pulley with three ropes is one.
is incorrect. It is 3
Qué velocidad –en m/s– tiene un móvil, que recorre 15 km en 20 minutos
(es para hoy por faaaa)
Answers
Answer:
Explanation:
15 km(1000 m / km) / (20 min(60 s/min)) = 12.5 m/s
Physics!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
What is the formula for calculating distance?
QA: Speed x Time -- Speed/Time -- Time/Speed
Answers
Answer:
x=v.t
The answer: Distance= Speed x Time
And also
Time = Distance/Speed
Speed= Distance/Time
The diagram shows the velocity-time graph for a car travelling in a straight line along a road. Calculate the acceleration between t = 2.0 s and t = 5.0 s.
Answers
Answer:
a = Δv/Δt = (0 - 20) / (5 - 2) = -6⅔ m/s²
just this last one!!
A car slams on its brakes creating an acceleration of -4.7 m/s^2. It comes to rest after traveling a distance of 235 m. What was its velocity before it began to accelerate?
Answers
Answer:
[tex]47 \ \frac{m}{s}[/tex]
Explanation:
s = displacement (m)
u = initial velocity [tex](\frac{m}{s})[/tex]
v = final velocity [tex](\frac{m}{s})[/tex]
a = acceleration [tex](\frac{m}{s^{2} })[/tex]
t = time (s)
s = 235
a = -4.7
v = 0
v² = u² + 2as
(0)² = u² + 2(-4.7)(235)
u² - 2209 = 0
u² = 2209
u = 47
Answer:
[tex]\boxed {\boxed {\sf 47 \ m/s}}[/tex]
Explanation:
We are asked to find the initial velocity of the car before it began to accelerate.
We are given the acceleration, distance, and final velocity, so we will use the following kinematic equation:
[tex]{v_f}^2 = {v_i}^2 + 2ad[/tex]
The car's acceleration is -4.7 meters per second square. It traveled a distance of 235 meters. It came to rest, or a final velocity of 0 meters per second.
a= -4.7 m/s²d= 235 m [tex]v_f[/tex]= 0 m/sSubstitute the values into the formula.
[tex](0 \ m/s)^2 = {v_i}^2 + 2 (-4.7 \ m/s^2)(235 \ m)[/tex]
[tex]0 = {v_i}^2 + 2 (-4.7 \ m/s^2)(235 \ m)[/tex]
Multiply the numbers in parentheses.
[tex]0= {v_i}^2 + (-2209 \ m^2 / s^2)[/tex]
Add -2209 to both sides of the equation.
[tex]0+ 2209 \ m^2 /s^2 = {v_i}^2+ ( -2209 \ m^2 /s^2 )+ 2209 \ m^2 /s^2[/tex]
[tex]2209 \ m^2 /s^2 = {v_i}^2[/tex]
Take the square root of both sides.
[tex]\sqrt {2209 \ m^2 /s^2} = \sqrt {{v_i}^2[/tex]
[tex]\sqrt {2209 \ m^2 /s^2} = v_i[/tex]
[tex]47 \ m/s = v_i[/tex]
The inital velocity of the car was 47 meters per second.
Which object would have more momentum?
A 2 kg ball rolling at 4 m/s
A 5 kg ball rolling at 2 m/s
(Hint: Use momentum = mass * velocity)
a
Not enough information to determine which ball has more momentum.
b
They have the same momentum.
c
The 2 kg ball will have more momentum.
d
The 5 kg ball will have more momentum.
Answers
Answer:
b is the ans......
Explanation:
"b" (and any subsequent words) was ignored because we limit queries to 32 words.
K
Mission CG9: Weightlessness
Consider the several locations along a roller coaster
track. In which location(s) would the riders feel less
than their normal weight? Select all that apply.
Location A
Location B
Location C
a
=-10 m/s/s, dn
--2 m/s/s, up
a--6 m/s/s, dn
Location D
Location E
x=-12 m/s/s, dn
---6 m/s/s, up
Answers
The locations where the riders feel less than their normal weight are Location A, Location C and Location D.
The given parameters;
Location A, a = 10 m/s² downLocation B, a = 2 m/s² upLocation C, a = 6 m/s² downLocation D, a = 12 m/s² downLocation E, a = 6 m/s² upThe normal weight of the riders is calculated by applying Newton's second law of motion as follows;
W = mg
W = 9.8m
The apparent weight of the riders for the upward acceleration is calculated as follows;
[tex]R = m(g + a)[/tex]
The apparent weight of the riders for the downward acceleration is calculated as follows;
[tex]R = m(g - a)[/tex]
The apparent weight of the riders at location A is calculated as follows;
[tex]R_ A = m(9.8 - 10)\\\\R_ A = -0.2 m[/tex]
The apparent weight of the riders at location B is calculated as follows;
[tex]R_B = m(9.8 + 2)\\\\R_B = 11.8 m[/tex]
The apparent weight of the riders at location C is calculated as follows;
[tex]R_C = m(9.8 - 6)\\\\R_C = 3.8 m[/tex]
The apparent weight of the riders at location D is calculated as follows;
[tex]R_D = m(9.8 - 12)\\\\R_D = -2.2 m[/tex]
The apparent weight of the riders at location E is calculated as follows;
[tex]R_E = m(9.8 + 6)\\\\R_E = 15.8 m[/tex]
Thus, the locations where the riders feel less than their normal weight are;
Location ALocation CLocation D.Learn more about Newton's second law and reading of a scale here: https://brainly.com/question/11603452
What is the mass of a school bus if it can accelerate from rest to 15.5 m/s over 8.25
s with 7,500 N of force?
128 kg
3991 kg
0.017 kg
14,091 kg
Answers
The mass of a school bus if it can accelerate from rest to 15.5 m/s over 8.25s with 7,500 N of force is 3989.4kg.
HOW TO CALCULATE MASS:
The mass of an object can be calculated by dividing the force applied to the object by its acceleration. According to this question, a bus can accelerate from rest to 15.5 m/s over 8.25s. The acceleration can be calculated as follows:a = (v - u)/ta = 15.5 - 0/8.25a = 15.5/8.25a = 1.88m/s²The mass of the bus = 7500N ÷ 1.88m/s²The mass of the bus = 3989.4kgTherefore, the mass of a school bus if it can accelerate from rest to 15.5 m/s over 8.25s with 7,500 N of force is 3989.4kg.Learn more about mass at: https://brainly.com/question/20259048?referrer=searchResults
A racing car traveling with constant increases its speed from 10 m/s; 30 m/s over a distance of 60 mlong does this take? to
Answers
Answer:
Explanation:
constant acceleration???
assume it to be so
average speed is (10 + 30) / 2 = 20 m/s
t = d/v = 60/20 = 3 s
An object is projected with speed of 4ms at an angle of 60° to horizontal. Calculate the time of flight of the object. (g=10ms2)
Answers
0.8 seconds
Explanation:
time of flight = 2u/g
u=4m/s
g=10
= 8/10
= 0.8 sec
just a trial...not sure!!!
Given :
∅ = 60⁰
u = 4 m/s
g = 10m/s²
to find :
T = ?
Solution :
as per formula,
[tex]t = \frac{2u \: sin \theta}{g} [/tex]
now put the value : [tex]t \: = \frac{2 \times 4 \times sin \: 60}{10} [/tex]
as we know [tex] sin60 \: = \frac{ \sqrt{3} }{2} [/tex]
therefore,
[tex]t \: = \frac{8 \times \frac{ \sqrt{3} }{2} }{10} [/tex]
as we solve this we get,
[tex]t \: = \frac{ 2\sqrt{3} }{5} [/tex]
that's t = 0.69 sec
[tex]\sf\fbox\red{\:I \:hope \:it's \:helpful \:to \:you}[/tex]
Which of these is Newton's 3rd law of motion?
Equal and opposite forces
F = m x a
Inertia
Gravity
Answers
define parking orbit?
Answers
Answer:
An orbit of a spacecraft from which the spacecraft or another vehicle may be launched on a new trajectory.
which statement about metals is true?
Answers
All metals are solid at (our) living temperatures except for mercury which is a liquid. Metals are shiny for a while at least when properly finished. Metals are good conductors of both heat and electricity. This is due to the excess electrons in their valence clouds that facilitate energy transfer.What are 5 characteristics of metal?
Metals are lustrous, malleable, ductile, good conductors of heat and electricity
Silver conducts electricity better than any other metal.
Brass is an alloy made from zinc and copper.
Pure gold is too soft for many things so most gold is combined with other metals to make it stronger. ...
World time periods are often listed by the metal used.
Tony brought 9 2/3pitchers of juice to a volleyball game, and the players drank3 7/8pitchers of it. How much juice is left?
Answers
Rewrite the amounts as improper fractions:
9 2/3 = 29/3
3 7/8 = 31/8
Rewrite both fractions with a common denominator
29/3 = 232/24
31/8 = 93/24
Now subtract: 232/24 - 93/24 = 139/24
Rewrite as a proper fraction: 5 19/24
Answer 5 19/24
write 2 situations in which the energy changes mentioned occur
Answers
Answer:
The types of energy is bond breaking and bond forming in chemical energy.
Explanation:
During Chemical reaction energy is required either for breaking up bonds in case of reactants and building bonds to form products.
The chemical reaction in which energy is released is called exothermic reactions, which is released due to making up the bonds.
The chemical reaction in which energy is absorbed is called endothermic reactions, in which energy is absorbed for breaking up the bonds.
What causes the difference in the angle of the sun on the Earth's surface throughout the year?
Answers
Answer:
The axis is tilted and points to the North Star no matter where Earth is in its orbit. Because of this, the distribution of the Sun's rays changes. ... It also means that the angle at which sunlight strikes different parts of Earth's surface changes through the year.
Explanation:
Pls sub to bdoggaming if this helped
A 40-kg worker climbs a ladder upwards for 15m. What work was done during their climb upwards?
Answers
Answer:
Explanation:
The work increased the potential energy
W = PE = mgh = 40(9.8)(15) = 5880 J(oules)
Chronic diseases are also know as
Answers
Answer:
Chronic Condition or Long-term Illness
Explanation:
They can also be known as Chronic Conditions or Long-Term Illnesses, hope this helps.
Answer:
Chronic condition, also called long-term condition.
Explanation:
The number of wavelengths that pass a fixed point on a wave is called ______?
Answers
Explanation:
it's called a wave frequency
im pretty sure but than again I'm in Middle School but just trust me
Answer:
wave frequency i think. hope its helps
Which of these do not affect fluid friction?
The surface of an object
The viscosity (thickness) of fluid an object is in
The shape of an object
The weight of an object
Answers
Hope that helps
You are investigating how objects move when they are dropped from different heights. To collect your data, you drop a 1 kg weight from different heights and record the time it takes for the object to hit the ground when dropped from different heights. The data you collect is shown below:
Height dropped (m)
Time to fall (s)
1.0
0.45
2.0
0.63
3.0
0.78
4.0
0.89
Next, you plan to drop a 5 kg weight from the same heights. How will your time values in your new data table for the 5 kg weight compare to the time values in the old data table for the 1 kg weight?
Answers
The time of motion of the 5 kg object will be the same as 1 kg since both objects are dropped from the same height.
The given parameters;
Mass of the first object, m1 = 1 kg
Mass of the second object, m2 = 5 kg
The final velocity of the objects during the downward motion is calculated as follows;
[tex]v_f = v_0 + gt\\\\v_f = 0 + gt\\\\\v_f = gt[/tex]
The time of motion of the object from the given height is calculated as;
[tex]h = v_0 t + \frac{1}{2} gt^2\\\\h = 0 + \frac{1}{2} gt^2\\\\h = \frac{1}{2} gt^2\\\\gt^2 = 2h\\\\t^2 = \frac{2h}{g} \\\\t = \sqrt{\frac{2h}{g} }[/tex]
The time of motion of each object is independent of mass of the object.
Thus, the time of motion of the 5 kg object will be the same as 1 kg since both objects are dropped from the same height.
Learn more about time of motion here: https://brainly.com/question/2364404