physics
posted by Anonymous
Mary applies a force of 77 N to push a box with an acceleration of 0.45 m/s2. When she increases the pushing force to 82 N, the box's acceleration changes to 0.74 m/s2. There is a constant friction force present between the floor and the box.
(a) What is the mass of the box?

Henry
FapFk = m*a
Eq1: 77  Fk = m*0.45
Eq2: 82  Fk = m*0.74
Subtract Eq2 from Eq1:
Diff. = 5 = 29m
m = 0.172 kg.
Respond to this Question
Similar Questions

physics
because of friction, a constant force of 20 N is needed to slide a box across a room to the right at a constant speed, and box is moved 3 m. What is the friction force and how much work is done by friction force? 
physics
You push a box along the floor against a constant force of friction. When you push with a horizontal force of 75 N the acceleration of the box is 0.55 m/s2; when you increase the force to 85 N the acceleration is 0.78 m/s2. (a) Find … 
Physics
You push a box along the floor against a constant force of friction. When you push with a horizontal force of 72 N the acceleration of the box is 0.43 m/s2; when you increase the force to 77 N the acceleration is 0.58 m/s2. (a) Find … 
Physics
A box of mass m1 = 10.0 kg rests on a smooth, horizontal floor next to a box of mass m2 = 5.0kg. You push on the box 1 with a horizontal force of F = 31.8 N: a.)What net force on box 2 will cause it to have this acceleration? 
Physics
You push a box along the floor against a constant force of friction. When you push with a horizontal force of 78 N the acceleration of the box is 0.46 m/s2; when you increase the force to 86 N the acceleration is 0.76 m/s2. (a) Find … 
Physics
A 30.0 kg box is being pulled across a carpeted floor by a horizontal force of 230 N., against a friction force of 210 N. Calculate the acceleration of the box and find the x and y components of the acceleration of the box. Align the … 
physics MC QUESTIONS
1. You push a block up a ramp with friction. The block is moving at constant speed ? 
physics
Could anyone help me set up this equation? 
physics
Mary applies a force of 71 N to push a box with an acceleration of 0.57 m/s2. When she increases the pushing force to 83 N, the box's acceleration changes to 0.86 m/s2. There is a constant friction force present between the floor and … 
AP Physics
A large box has a mass of 500kg and the coefficient of static friction for the box and the floor is 0.45, and the coefficient of kinetic friction is 0.30. a. What is the minimum horizontal force needed to get the box moving?