Answer:
[tex]\mu_s=0.51[/tex]
Explanation:
Coefficient of friction
The static coefficient of friction is a measure of the force needed to start moving an object from rest along a rough surface.
It's calculated as:
[tex]\displaystyle \mu_s=\frac{F_r}{N}[/tex]
Where Fr is the friction force and N is the normal force exerted by the surface over the object.
In the absence of any other vertical force, the normal is equal to the weight of the object:
[tex]N = W = m.g[/tex]
The box has a mass of m=80 Kg, thus the normal force is:
[tex]N = 80\ Kg * 9.8\ m/s^2[/tex]
N = 784 N
The student needs to push with a force of 400 N to make the box move. That is the force that barely outcomes the friction force. Thus:
[tex]F_r=400\ N[/tex]
Calculating the coefficient:
[tex]\displaystyle \mu_s=\frac{400}{784}[/tex]
[tex]\mathbf{\mu_s=0.51}[/tex]
sandra wants to lower her body fat percentage which choices will help her reach her goal
Sandra can take to lower her body fat percentage to eat several, balanced, low-calorie meals throughout the day and to exercise regularly.
What is body fat?When we can't access food for a lengthy period of time, fat is a vital source of stored energy.
There are several steps Sandra can take to lower her body fat percentage:
Exercise regularly: Regular physical activity, such as cardiovascular exercise, resistance training, and high-intensity interval training (HIIT), can help increase muscle mass and reduce body fat.
Eat a healthy diet: Eating a balanced diet that includes plenty of fruits, vegetables, whole grains, lean proteins, and healthy fats can help Sandra maintain a calorie deficit, which is necessary for reducing body fat. Avoiding processed foods, added sugars, and excessive amounts of saturated and trans fats can also be beneficial.
Control portions: Paying attention to portion sizes can help Sandra avoid overeating and maintain a calorie deficit. She can also use tools like measuring cups and a food scale to help control portion sizes.
Stay hydrated: Drinking enough water can help Sandra maintain a healthy metabolism and reduce feelings of hunger.
Get enough sleep: Getting adequate sleep (7-9 hours per night) can help regulate hormones that impact metabolism and hunger, making it easier to maintain a calorie deficit and reduce body fat.
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You are currently getting 26 sales opportunities per day and closing 64% of them. How many sale opportunists per day?
Answer: 16
Explanation:
Finish the sentence below.
Jack just met up with the bois to. . .
Answer:
cook some hamburgers and go fishing
Explanation:
Answer:
go to the baseball game and have fun
Explanation:
what is the correct term for the people who came before us?
Answer:
Ancestors!
Explanation:
I know a thing or two~
Answer:
It depends on what the context is, if you mean people that came long before us you might be refering to ancestors, but if you mean people that came before us at any time then you would be refering to a predecessor.
Explanation:
Consider a polymer formed by a chain process. By how much does the kinetic chain length change if the concentration of initiator decreases by a factor of 10.0 and the concentration of monomer increases by a factor of 5.0?
At time t = 0.00 s, a car is traveling along a straight line at a speed of 10 m/s with constant acceleration. The car travels 46.0 m during the time interval between t = 2.00 s and t = 4.00 s. What is the acceleration of the car?At time t = 0.00 s, a car is traveling along a straight line at a speed of 10 m/s with constant acceleration. The car travels 46.0 m during the time interval between t = 2.00 s and t = 4.00 s. What is the acceleration of the car?
Answer:
0.00
Explanation:
The second floor of a house is 6 m above the street level. How much work is required to lift a 300-kg refrigerator to the second-story level?
Answer:
Work done, W = 18 kJ
Explanation:
Given that,
The mass of a refrigerator, m = 300 kg
The second floor of a house is 6 m above the street level.
We need to find the work required to lift the refrigerator to the second-story level.
Work done, W = F × d
Putting all the values,
W = 300 × 10 × 6
W = 18000 J
or
W = 18 kJ
So, 18 kJ of work is done in lifting the refrigerator to the second-story level.
Humpback whales sometimes catch fish by swimming rapidly in a circle, blowing a curtain of bubbles that confuses a school of fish and traps it in a small area, where the whales can easily catch and eat them. Suppose a 25,000-kg humpback whale swims at 2.0 m/s in a circle of radius 8.2 m. What centripetal force must the whale generate?
Answer:
1.2 x [tex]10^4[/tex] N
Explanation:
The centripetal force of a body moving in a circle is given by:
Centripetal force = [tex]\frac{Mv^2}{r}[/tex]
where M = mass of the object, v = velocity with which the object is moving, and r = radius of the circle.
In this case, M = 25,000 kg, v = 2.0 m/s, and r = 8.2 m. Hence;
Centripetal force generated by the whale = 25,000 x 2^2/8.2
= 12,195.12 N = 1.2 x [tex]10^4[/tex] N to two significant digits.
What total distance did this student travel?
Seems like some of your question is missin
Explanation:
A car traveling 13 m/s to the north collides with a car traveling 19 m/s to the
south. Each car has a mass of 1250 kg. If the system is defined as the two
cars, what is the change in momentum of the system due to the collision?
A. 0 kg*m/s
B. 40,000 kg*m/s
O c. 16,250 kg-m/s
D. 23,750 kg-m/s
Answer: 0kg(m/s)
Explanation:
An object is thrown straight down with an initial speed of 4 m/s from a window which is 8 m above the ground. Calculate: a) The time it takes the object to reach the ground b) Its velocity when it reaches the ground.
Answer:
0.41s
8.01m/s
Explanation:
Using the formula; v = u + at
Where;
u = initial velocity (m/s)
v = final velocity (m/s)
t = time (s)
a = acceleration (m/s²)
According to the provided information, u = 4m/s, s = 8m,
V = u + at
4 = 0 + 9.8t
4 = 9.8t
t = 0.41s
b) v = u + at
v = 4 + 9.8(0.41)
v = 4 + 4.018
v = 8.018m/s
Why do you think the objects in each collision experience a different change in velocity?
Answer:
In a collision, there is a collision force which endures for some amount of time to cause an impulse. This impulse acts upon the object to change its velocity and thus its momentum
1. Find the period of a tuning fork that vibrates 120 times/sec.?? I will give brainlest
Answer:
it the last one
Explanation:
What is the definition of kepal law
A pan of water is sitting on an electie over the stove is then turned on to high What will happen to the movement of the particles in the pan?
The particles that make up the pan will move closer together
The parties that make up the pan will not be affected
The particles that make up the pan will speed up
The partides that make up the pan will slow down
Answer:
The particles that make up the pan will speed up
Explanation:
A 1000kg car is moving with a speed of 20m/s. Determine the net work required to move the
vehicle to a speed of 30m/s?
Answer:
250,000 Joules
Explanation:
The work required is the amount of energy added, so the answer is the difference in kinetic energy before and after the acceleration of the car. (The problem doesn't say it's flat where the car is, but well assume it since there is no information about an elevation change that would require us to concern ourselves with potential energy!)
W = E_final - E_initial
= 1/2 m v_final^2 - 1/2 m v_initial^2
= 1/2 m (v_final^2 - v_initial^2)
= 1/2 (1000 kg) ( (30 m/s)^2 - (20 m/s^2) )
= 1/2 (1000 kg) (500 m^2/s^2)
= 250,000 kg m^2/s^2
= 250,000 Joules
List the location in order from lear to greatest pressure
At standard temperature and pressure, carbon dioxide has a density of 1.98 kg/m3. What volume does 1.70 kg of carbon dioxide occupy at standard temperature and pressure?
Answer:
volume= 0.85m^3Explanation:
The density of a substance is defined as the mass per unit volume of the substance, the unit is in kg/m^3 and it is represented by the greek letter rho
Step one:
given data
we are told that the density of Co2= 1.98 kg/m3
and the mass of Co2 is= 1.70 kg
we know the relation between mass, volume and density is
[tex]density=mass/volume[/tex]
make volume subject of formula we have
[tex]volume=mass/density[/tex]
substitute we have
[tex]volume=1.7/1.98\\\\volume= 0.85m^3[/tex]
In a few sentences, describe why abstinence is the best choice to prevent the consequences of sexual activity. (health)
Answer:
Abstinence is the best choice to prevent the consequences of sexual activity because you're putting yourself at lower risk to encounter STD's and STI's. Abstinence also prevents you from getting pregnant.
Explanation:
I got 100% on Edge.
Complete abstinence is the best choice to prevent the consequences of sexual activity because this prevents any type of sexual contact and STDs.
What is Abstinence?Abstinence is a self-enforced restraint from the indulging in bodily activities which are widely experienced as giving pleasure to people. Most frequently, abstinence refers to sexual abstinence, however it can also mean abstinence from alcohol, drugs, food, etc.
Complete abstinence is the only way which can guarantee protection against the infection with sexually transmitted diseases. This means avoiding all the types of intimate genital contact. Someone who is practicing complete abstinence does not have any type of intimate sexual contact. So, there is no risk of getting an STD.
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When I mix 200g of water at 10°C with 300g of water at 55°C, what is the final temperature of the mixture?
Answer:
4th of August is the
Explanation:
5th and then I can help out by getting
ervation of Mass Review Add-ons Help Last edit was 31 minutes ago Arial 11 + B I U A EE 1 12 3 4 4) In a closed system, a chemical reaction takes place. The mass of the reactants in the beginning of the reaction is 32g. What does the mass have to be in the end of the reaction in order to follow the law of conservation of mass?
Answer:
It has to be 32g
Explanation:
Mass at the beginning of the reaction is 32g
To ensure the law of conservation of mass, the mass at the beginning and end of the reaction must be the same.
The law of conservation of mass states that "matter is neither created nor destroyed but atoms combines with one another" .
So, if a reaction starts with 32g it must end with 32g
Which of the following scenarios best describes Newton's law of action-reaction?
F A bottle of soda sitting in the console of a vehicle appears to move left as the vehicle makes a sharp
right turn.
A rocket moves upward as the engine pushes downward against exhaust gases and the exhaust gases
push upward against the engine.
H
A train traveling 88 kilometers per hour takes approximately one mile to come to a complete stop.
J
An ice skater sharpens the blades of their skates to lessen the effect of friction.
A rocket moves upward as the engine pushes downward against exhaust gases and the exhaust gases push upward against the engine.
How high will a cannonball reach if fired straight up out of a cannon at an initial upward velocity of
120m/s?
Answer:
720 m
Explanation:
Taking the upward direction as positive
We are given:
Initial vertical velocity of the cannonball = 120 m/s
Vertical acceleration of the cannonball = -10 m/s²
Final velocity of the Cannonball = 0 m/s [at the maximum height, the velocity of the ball will be 0 m/s for a moment]
Maximum height of the ball:
v² - u² = 2as [Third equation of motion]
replacing the variables (s is the maximum height)
(0)² - (120)² = 2(-10)(s)
-14400 = -20s
s = -14400 / -20 [Dividing both sides by -20]
s = 720 m
Hence, the maximum height of the Cannonball fired vertically at a velocity of 120 m/s is 720 m
About how much greater is the gravitational force exerted by the moon on the near side of the earth than on the far side? Choose one of the Following:
(a) About 2% greater
(b) About 7% greater
(c) About 11% greater
(d) About 15% greater
Solution :
Distance between the Earth and the moon, D = [tex]$3.84 \times 10^8 \ m$[/tex]
Radius of the earth, r = [tex]$6.37 \times 10^6 \ m$[/tex]
Gravitational force on the near side of the moon, [tex]$F_N = \frac{GM_m m}{(D-r)^2}$[/tex] ......(1)
Gravitational force on the far side of the moon, [tex]$F_F = \frac{GM_m m}{(D+r)^2}$[/tex] ..............(2)
where, [tex]$M_m$[/tex] = mass of moon
m = mass of the near side and far side respectively (both are taken as equal)
Therefore,
[tex]$\frac{F_N-F_F}{F_N}\times 100 = \frac{\frac{GM_m m}{D-r}^2-\frac{GM_m m}{D+r}^2}{\frac{GM_m m}{D-r}^2} \times 100 $[/tex]
[tex]$=1 - \frac{(D-r)^2}{(D+r)^2} \times 100$[/tex]
[tex]$=1- \left(\frac{1-\frac{r}{D}}{1+\frac{r}{D}}\right)^2 \times 100$[/tex]
[tex]$= 1- \left(\frac{0.98}{1.02}\right)^2 \times 100$[/tex]
= 7%
Hence, correct option is (b) About 7% greater
What is inertia?
An object's tendency to move quicker
An object's tendency to change direction
An object's tendency to resist changes in motion
An unbalanced force on an object
Answer:
I think the answer should be an object's tendency to resist changes in motion.
Explanation:
Inertia is resistance of any physical object to any changes in its velocity.
Answer:
an object's tendency to resist changes in motion.
Explanation:
Question 4 of 10
How does the electric current of an AC generator differ from that of a DC
generator?
O A. It is much stronger.
OB. It flows through the permanent magnets.
C. It is much weaker.
D. It constantly reverses direction.
Answer:
D) it constantly reverses direction
Explanation:
Just took the test
What is the final speed of a free electron accelerated from rest through a potential difference of -120 V? The mass of the electron is 9.11x10-31kg. You need to express the speed in km/s.
You should round your answer to an integer, indicate only the number, do not include the unit.
Answer:
The final speed of the electron is 6,497 km/s
Explanation:
Given;
mass of the electron, m = 9.11 x 10⁻³¹ kg
electron potential, V = -120 V
Apply work energy theorem;
¹/₂mv² = eV
Where;
v is the final speed of the electron
e is the charge of the electron, = 1.602 x 10⁻¹⁹ C
[tex]v = \sqrt{\frac{2eV}{m} }\\\\v = \sqrt{\frac{2(1.602*10^{-19})(120)}{9.11*10^{-31}} }\\\\v = 6496473.75 \ m/s\\\\v = 6,497 \ km/s[/tex]
Therefore, the final speed of the electron is 6,497 km/s
how many significant figures does 1700000000 have ?
Answer:
2 sig
Explanation:
1 and 7
23)
What statement BEST describes a gas?
A)
Gases have definite shape and variable volume.
B)
Gases have variable shape and variable volume.
0
Gases have a definite shape and definite volume.
D)
Gases have a variable shape and definite volume.
Answer:
b
Explanation:
A ball of clay is moving at a speed of 12 m/s collides and sticks to a stationary ball of clay. If each ball has a mass of 13 kg, what's the combined velocity of the two balls of clay after the collision
Answer:
p_{f} = 6 m / s
Explanation:
We can solve this exercise using conservation of momentum. For this we define a system formed by the two balls, so that the forces during the collision have been intense and the moment is preserved
Initial instant. Before the crash
p₀ = m v +0
Final moment. Right after the crash
[tex]p_{f}[/tex] = (m + m) v_{f}
how the moment is preserved
p₀ = p_{f}
m v = 2 m v_{f}
v_{f} = v / 2
we calculate
v_{f} = 12/2
p_{f} = 6 m / s