Answer:
[tex]9\:\mathrm{J}[/tex]
Explanation:
Kinetic energy is given by the following equation:
[tex]KE=\frac{1}{2}mv^2[/tex], where [tex]m[/tex] is mass in [tex]\mathrm{kg}[/tex] and [tex]v[/tex] is velocity in [tex]\mathrm{m/s}[/tex].
Since the cell phone's mass is given in grams, we need to convert this into kilograms:
[tex]80\:\mathrm{g}\cdot \frac{1\:\mathrm{kg}}{1000\:\mathrm{g}}=0.08\:\mathrm{kg}[/tex].
Therefore, the kinetic energy of the cell phone is:
[tex]KE=\frac{1}{2}\cdot 0.08\cdot 15^2=\fbox{$9\:\mathrm{J}$}[/tex].
Bob needs to accelerate a 4 kg box at 2 m/s2. How much force does he need to use?
Answer:
8 N
Explanation:
From Newtons second law of motion, we have;
F = ma
where: F is the force applied, m is the mass of the object, and a is its acceleration.
From the given question: mass of box = 4 kg and acceleration of the box = 2 m/[tex]s^{2}[/tex], then;
F = 4 x 2
= 8
F = 8 N
The amount of force to be used is 8 N.
Calculate the approximate value for the distance travelled in the first 10 s by using the above graph
Answer:
80 m
Explanation:
From the question given above, the following data were obtained:
Speed = 8 m/s
Time = 10 s
Distance =?
Speed can be defined as the distance travelled per unit time. Mathematically, it can be expressed as:
Speed = Distance / time
With the above formula, we can obtain the distance travelled as illustrated below:
Speed = 8 m/s
Time = 10 s
Distance =?
Speed = Distance / time
8 = Distance / 10
Cross multiply
Distance = 8 × 10
Distance = 80 m
Therefore, the distance travelled is 80 m
In the picture shown below A represents a characteristic of only geocentric model, B represents a characteristic common to both geocentric and heliocentric models, C represents a characteristic of only heliocentric model, and D represents a characteristic which the geocentric and heliocentric models do not have.
Under which label will the characteristic, "The sun and planets revolve around a central moon in the solar system" fall?
A
B
C
D
When a glass rod is rubbed with silk, the silk becomes negatively charged. Which of the following explanations best describes that is happening?
a. Electrons move from silk to glass
b. Electrons move from glass to silk
c. Protons move from silk to glass
d. Protons move from glass to silk
Answer: b. Electrons move from glass to silk
Explanation:
When the glass rod is rub over against the silk, the glass loses the electrons due to the physical contact with the silk and the friction so produced. The surface of the glass becomes positively charged and the surface of the silk becomes negatively charged. As the surface of the glass loses electrons which are accepted by the silk surface.
You are standing next to a table and looking down on a record player sitting on the table. Take the spindle (axis of rotation) to be the center of your coordinate system and the y axis to be perpendicular to the side of the player you are standing next to. Long-playing records revolve 33(1/3) times per minute. You put a small blob of clay at the edge of a record that has a radius of 0.15 m, positioning the clay such that it is at its greatest value of y at t = 0.
Equation of motion for the y component of the clay's position: y(t)=Asin(ωt+ϕi)
Required:
a. What is the rotational speed of the clay?
b. Determine the value of A in the equation of motion.
c. Determine the value of ϕi in the equation of motion. Suppose that −π<ϕi≤π
Answer:
a) the rotational speed of the clay is 3.45 rad/s
b) the value of A in the equation of motion is 0.15 m
c) the value of ϕi is 90° or π/2 rad.
Explanation:
Given that;
Revolution per minute rpm = 33( 1/3) = 100/3
The frequency f = 100 / 3(60) = 0.55 Hz
a)
Rotational speed W = 2πf
we substitute
W = 2π × 0.55
W = 3.45 rad/s
Therefore, the rotational speed of the clay is 3.45 rad/s
b)
given equation; y(t)=Asin(ωt+ϕi)
given that radius = 0.15 m
y(t)=(0.2)sin(ωt+ϕi)
Therefore, the value of A in the equation of motion is 0.15 m
c)
since y(t) has the maximum value at t =0
so at t=0
y(0) = (0.15)sin(ω(0)+ϕi)
= 0.15sin(ϕi)
this will give maximum value when ϕi = 90°
so
y(0) = (0.15)sin(ω(0)+ϕi)
= 0.15sin(90°)
= 0.15
hence, the value of ϕi is 90° or π/2 rad.
The chart below summarizes the forces applied to four different objects.
Which object will experience the greatest acceleration?
A. Z
B. X
C. Y
D. W
Answer:
C. Y
Explanation:
From Newton's second law of motion, we know that:
Force = mass x acceleration
So;
acceleration = [tex]\frac{Force }{mass}[/tex]
Therefore, to have the highest acceleration at a constant force, the mass must be low. Acceleration is inversely proportional to mass.
Y has the least mass and it will have the highest acceleration
we had to drive 150 miles to the hotel we left at 1 p.m. and got there at 4 p.m. what is our average speed
Answer:
Our average speed was 50 mph
Explanation:
Constant Speed Motion
An object is said to travel at constant speed if the ratio of the distance traveled by the time taken is constant.
Expressed in a simple equation, we have:
[tex]\displaystyle v=\frac{d}{t}[/tex]
The distance we had to drive is d=150 miles. If we left at 1 p.m. and got to the hotel at 4 p.m. This means we took t=3 hours to get there.
The average speed is:
[tex]\displaystyle v=\frac{150\ miles}{3\ h}[/tex]
[tex]v=50\ mi/h[/tex]
Our average speed was 50 mph
Do it in order.
from smallest to largest
Answer:
The earth, The sun, the solar system and the milky way.
How does heat from the sun get to earth?
if an electric is not grounded, it is best to reach out and touch it to provide the ground
Answer:
No. Touching a live electric current is never a good idea.
Answer:
false you would electrocute yourself
Explanation:
!!!!!!!!!!! LOGICAL !!!!!!!!!
Unconfined water comes straight from the surface and is more
A rock is thrown directly upward from the edge of a flat roof of a building that is 56.3 meters tall. The rock misses the building on its way down, and is observed to strike the ground 4.00 seconds after being thrown. Take the acceleration due to gravity to have magnitude and neglect any effects of air resistance. With what speed was the rock thrown
The gauge pressure at the bottom of a cylinder of liquid is pg = 0.40 atm. The liquid is poured into another cylinder with twice the radius of the first cylinder. What is the gauge pressure at the bottom of the second cylinder?
Answer:
Explanation:
gauge pressure due to a liquid column of density d and height h is given by the following expression .
P = hdg
The pressure depends upon height of liquid column and not on the cross sectional area .
In first cylinder .
gauge pressure = .40 atm
hdg = .40 atm
cross sectional area of cylinder = π r²
The radius of second cylinder is twice of the first , cross sectional area will be 4 times .
The volume remains the same when the liquid is poured into second cylinder
volume = cross sectional area x height .
As cross sectional area of second cylinder is 4 times , height of liquid column in second cylinder = h / 4 .
gauge pressure in second cylinder = h / 4 x d x g = hdg / 4
.40 / 4 = .10 atm
gauge pressure in second cylinder = .10 atm.
____ is factual information not subject to bias.
Interpretation
Analysis
Data
Opinion
Answer:
Data
Explanation:
Data is factual information not subject to bias.
This ultimately implies that, data connotes fact, thus, it is an information that is credible, accurate, a statement of truth, evidential and proven.
In Computer programming, a data dictionary can be defined as a centralized collection of information on a specific data such as attributes, names, fields and definitions that are being used in a computer database system.
In a data dictionary, data elements are combined into records, which are meaningful combinations of data elements that are included in data flows or retained in data stores.
This ultimately implies that, a data dictionary found in a computer database system typically contains the records about all the data elements (objects) such as data relationships with other elements, ownership, type, size, primary keys etc. This records are stored and communicated to other data when required or needed.
What is the function
of second plate in
parallel plate capacitor?
what is the mass number of this element
Answer:
Which element?
U did not mention it
Kayla starts at -3, walks 5 blocks right and 3 blocks left. What is her displacement?
Answer: The displacement is 1 block.
Explanation:
Let's define:
The right is the positive side.
The left is the negative side.
Then if you start at position A, and you walk N blocks to the right, the new position is:
A + N
And if you start at position A, and you walk M blocks to the left, the new position is:
A - M.
In this case, we know that Kayla starts at -3 and she walks 5 blocks to the right.
Then her new position is:
-3 + 5 = 2
Now she walks 3 blocks to the left, then her new position is:
2 - 3 = -1
The displacement will be equal to the difference between the final position (-1) and the initial position (-2)
Then the displacement is:
D = -1 - (-2) = -1 +2 = 1
The displacement is 1 block.
HURRY What happened when the speed was increased?
Let A be the second to last digit and let B be the last two digits of your 8-digit student ID. Example: for 20245347, A = 4 and B = 47.A ball rolls off a table. The table top is 1.2 m above the floor and the ball lands 3.6 m from the base of the table. Determine the speed of the ball at the time it rolled over the edge of the table? Calculate the answer in m/s and rounded to three significant figures.
Answer:
7.35 m/s
Explanation:
Using y - y' = ut - 1/2gt², we find the time it takes the ball to fall from the 1.2 m table top and hit the floor.
y' = initial position of ball = 1.2 m, y = final position of ball = 0 m, u = initial vertical velocity of ball = 0 m/s, g = acceleration due to gravity = 9.8 m/s² and t = time taken for ball to hit the ground.
So, substituting the values of the variables into the equation, we have
y - y' = ut - 1/2gt²
0 - 1.2 m = (0 m/s)t - 1/2(9.8 m/s²)t²
- 1.2 m = 0 - (4.9 m/s²)t²
- 1.2 m = - (4.9 m/s²)t²
t² = - 1.2 m/- (4.9 m/s²)
t² = 0.245 s²
t = √(0.245 s²)
t = 0.49 s
Since d = vt where d = horizontal distance ball moves = 3.6 m, v = horizontal velocity of ball = unknown and t = time it takes ball to land = 0.49 s.
So, d = vt
v = d/t
= 3.6 m/0.49 s
= 7.35 m/s
Since the initial velocity of the ball is 7.35 m/s since the initial vertical velocity is 0 m/s.
It is shown thus V = √(u² + v²)
= √(0² + v²)
= √(0 + v²)
= √v²
= v
= 7.35 m/s
A 6.00-kg crate is suspended from the end of a short vertical rope of negligible mass. An upward force F(t) is applied to the end of the rope, and the height of the crate above its initial position is given by y(t)=(2.80m/s)t+(0.610m/s^3)t^3. What is the magnitude of F when t = 4.00 s?
Answer:
The magnitude of F when t=4 s=146.64 N
Explanation:
We are given that
Mass of crate,m=6.00 kg
Height of crate above its initial position is given by
[tex]y(t)=(2.80 m/s)t+(0.610 m/s^3)t^3[/tex]
We have to find the magnitude of F when t=4.00 s
Differentiate w.r.t t
[tex]\frac{dy}{dt]=2.8+3(0.61)t^2[/tex]
[tex]\frac{d^2y}{dt^2}=6(0.61)t[/tex]
[tex]a(t)=\frac{d^2y}{dt^2}=6(0.61)t m/s[/tex]
[tex]a(4)=6(0.61)(4)=14.64 m/s^2[/tex]
Now, magnitude of force
[tex]F=m(a+g)=6(14.64+9.8)=146.64N[/tex]
Hence, the magnitude of F when t=4 s=146.64 N
12 Rajiv made a model of a boat. When he places it in water, it sinks. According to
Archimedes' principle, why does the boat sink?
A The boat is too small.
B The buoyant force is less than the boat's weight.
C The buoyant force is equal to the boat's weight.
D The buoyant force is greater than the boat's weight.
Answer:
the answer is .D
Explanation:
force is greater than the boats weight
Answer: The buoyant force is less than the boats weight.
what is the formula for kinetic energy
Answer:
[tex]\boxed{\bold { \large { \boxed {KE=\frac{1}{2} mv^2}}}}[/tex]
Explanation:
Kinetic energy formula
[tex]\displaystyle KE=\frac{1}{2} mv^2[/tex]
[tex]\displaystyle KE \Rightarrow \sf kinetic \ energy \ (J)[/tex]
[tex]\displaystyle m \Rightarrow \sf mass \ (kg)[/tex]
[tex]\displaystyle v \Rightarrow \sf velocity \ (m/s)[/tex]
2) Given R = 3 ohms and R, = 1 ohm and V = 12 volts
I
a) Find the total resistance.
b) Find the current in the circuit:
c) Find the voltage drop in each resistor:
Answer:
a) because this is in series, we have:
the total resistance is 3 + 1 = 4 (ohm)
b) the curren in the circuit is 12/4 = 3 (A)
c) the voltage in R = 3 ohm is 3.3 = 9 (V)
the voltage in R = 1 ohm is 12 - 9 = 3 (V)
Explain how momentum is determined and conserved.
ASAP!!
Explanation:
Momentum is conserved in the collision. Momentum is conserved for any interaction between two objects occurring in an isolated system.
how to add an answer
How do pulleys help move objects?
Pulleys are powerful simple machines. They can change the direction of a force, which can make it much easier for us to move something. If we want to lift an object that weighs 10 kilograms one meter high, we can lift it straight up or we can use a pulley, so we can pull down on one end to lift the object up.
Answer:
Pulleys are powerful simple machines. They can change the direction of power, which can make it much easier for us to move something. If we want to lift an object that weighs 10 kilograms one meter high, we can lift it straight up or use a pulley, so we can pull one end down and lift the object.
Explanation:
calculate the average speed of talias car during the trip
Answer:
We're no strangers to love
You know the rules and so do I
A full commitment's what I'm thinking of
You wouldn't get this from any other guy
I just wanna tell you how I'm feeling
Gotta make you understand
Never gonna give you up
Never gonna let you down
Never gonna run around and desert you
Never gonna make you cry
Never gonna say goodbye
Never gonna tell a lie and hurt you
We've known each other for so long
Your heart's been aching but you're too shy to say it
Inside we both know what's been going on
We know the game and we're gonna play it
And if you ask me how I'm feeling
Don't tell me you're too blind to see
Never gonna give you up
Never gonna let you down
Never gonna run around and desert you
Never gonna make you cry
Never gonna say goodbye
Never gonna tell a lie and hurt you
No, I'm never gonna give you up
No, I'm never gonna let you down
No, I'll never run around and hurt you
Never, ever desert you
We've known each other for so long
Your heart's been aching but
Never gonna give you up
Never gonna let you down
Never gonna run around and desert you
Never gonna make you cry
Never gonna say goodbye
Never gonna tell a lie and hurt you
No, I'm never gonna give you up
No, I'm never gonna let you down
No, I'll never run around and hurt you
I'll never, ever desert you
Explanation:
RICK ROLLED
help me help me help me
An airplane travels 3100km at a speed of 790km/h, and then encounters a tailwind that boosts its speed to 990km/h for the next 2800 km. what was the total time for the trip? what was the average speed of the plane for this trip?
Answer:
6.75233 h
Explanation:
✓airplane travels 3100km at a speed of 790km/h,
Speed= distance/ time
Time= speed/distance
Distance=3100 km
Speed=790km/h
Time= 3100 /790
= 3.924 h
✓and then encounters a tailwind that boosts its speed to 990km/h for the next 2800 km
Time= 2800 k990km/h
= 2800/990
= 2.828 h
We can calculate total times as (3.924 + 2.828)
= 6.75233 h
what are ribosomes?
I'm tired. But I have insomnia. Big ugh moment. <.<.
Answer:
Ribosomes are organelles the make protein for the cell.