Question

Mary applies a force of 75 N to push a box with an acceleration of 0.43...

Mary applies a force of 75 N to push a box with an acceleration of 0.43 m/s2. When she increases the pushing force to 81 N, the box's acceleration changes to 0.63 m/s2. There is a constant friction force present between the floor and the box. (a) What is the mass of the box? kg (b) What is the coefficient of kinetic friction between the floor and the box?

(a) What is the mass of the box?
_________kg

(b) What is the coefficient of kinetic friction between the floor and the box?
__________

Homework Answers

Answer #1

According to the given problem,

constant force of kinetic friction = f
net force acting on box when it accelerates at 0.43 m/s² = F1 = 75 - f
net force acting on box when it accelerates at 0.63 m/s² = F2 = 81 - f
mass of box = F1/0.43 = (75-f)/0.42
mass of box = F2/0.63 = (81-f)/0.63
(75-f)/0.43 = (81-f)/0.63
0.63(75-f) = 0.43(81-f)
47.25 - 0.63f = 34.82 - 0.43f
0.2f = 12.42
f = 62.1 N
box mass = (75-62.1)/0.43 = 30 kg (a)
coefficient of kinetic friction = f/30g = 62.1/30(9.81) = 0.211 (b)

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Say you push on a 5 kg block with a force of Fa = 20 N,...
Say you push on a 5 kg block with a force of Fa = 20 N, at a 45° angle downward. The coefficient of kinetic friction between the block and the ground is ?k = 0.3. The coefficient of static friction is unknown, but it is known that ?s > 0.3. The block is moving with initial velocity to the right (the +x direction), v0 = 2 m/s. a) What is the magnitude of the force of friction on the...
a large box whose mass is 20.0 kg rests on the frictionless floor. A mover pushes...
a large box whose mass is 20.0 kg rests on the frictionless floor. A mover pushes on the box with a force of 250 N at an angle 35.0 below the horizontal. Draw the box's free body diagram and calculate the acceleration of the box b) if the kinetic friction coefficient is 0.1 between the box and floor. Draw the box's free body diagram and re-calculate the acceleration of the box
A factory worker exerts a 100 N horizontal pushing force on a 70.0 kg box that...
A factory worker exerts a 100 N horizontal pushing force on a 70.0 kg box that is initially at rest on the floor. The coefficient of static friction is 0.2 and the coefficient of kinetic friction is 0.1. The force of friction acting on the box is equal to:
A 1 kg. box is given a push so that it slides across the floor. How...
A 1 kg. box is given a push so that it slides across the floor. How far will it go, given that the coefficient of kinetic friction is 0.31 and the push imparts at initial speed of 3.1 m/s? Calculate to one decimal. Use g = 9.8 m/s2
A 1 kg. box is given a push so that it slides across the floor. How...
A 1 kg. box is given a push so that it slides across the floor. How far will it go, given that the coefficient of kinetic friction is 0.19 and the push imparts at initial speed of 5.4 m/s? Calculate to one decimal. Use g = 9.8 m/s2
A woman exerts a horizontal force of 107 N on a box with a mass of...
A woman exerts a horizontal force of 107 N on a box with a mass of 40.2 kg. (a) If the box doesn't move, what's the magnitude of the static friction force (in N)? N (b) What is the minimum possible value of the coefficient of static friction between the box and the floor? (Assume the box remains stationary.)
A box with mass m=5 (kg) is being pulled with force F=25 (N) horizontally and moves...
A box with mass m=5 (kg) is being pulled with force F=25 (N) horizontally and moves with constant speed. (g = 10 m/s2) a) How much is the coefficient of kinetic friction? b) How much is the Normal force excreted from surface to the box? c) If the box moves 10 (m) in 20 seconds, calculate the work done by force F and by friction. What is the power of Force F?
Mild-mannered Clark Kent pushes a box with a force F at an angle of 21° below...
Mild-mannered Clark Kent pushes a box with a force F at an angle of 21° below the horizontal. Find the force Clark Kent is required to push with to start the crate moving. The mass of the crate is m = 34 kg and the coefficient of static friction between the crate and the floor is 0.67. N
A man of 75 kg is pushing a heavy box along flat floor. The coefficient of...
A man of 75 kg is pushing a heavy box along flat floor. The coefficient of sliding friction between the floor and the box is 0.20, and the coefficient of static friction between the man's shoes and the floor is 0.80. (a) If the man pushes downward on the box at an angle of 30 degrees, what is the maximum mass of the box he can move? (b)If the man pushes upward on the box at an angle of 30...
A crate of 31.6-kg tools rests on a horizontal floor. You exert a gradually increasing horizontal...
A crate of 31.6-kg tools rests on a horizontal floor. You exert a gradually increasing horizontal push on it and observe that the crate just begins to move when your force exceeds 309 N . After that you must reduce your push to 248 N to keep it moving at a steady 22.0 cm/s What is the coefficient of static friction between the crate and the floor? What is the coefficient of kinetic friction between the crate and the floor?...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT