# physics helppp!

The coeffcient of friction between the 7.9 kg mass and the table is 0.55, and the coeffcient of friction between the 5 kg mass and the table is 0.38.
Consider the motion of the 37 kg mass
which descends by the amount of y = 0.45m after releasing the system from rest. The acceleration of gravity is 9.8 m/s2 : Find the work done against friction. Answer in units of J.
part2 Find the speed of the 37 kg mass. Answer in units of m/s.
part3
Find the time it takes for the 37 kg mass to fall a distance of y = 0.45 m.

Diagram: mass one on the left edge of table, mass 2 on middle of table and mass three handing down on a pulley on the right hand side of the table all connected by a string.

I am currently taking physics myself, so I'm not certain, but I can at least get you started on part 1.
Work = (Force) * (distance)
In this case, the force is friction, and the distance is .45m (if the 37kg mass falls .45m, the weights on table are pulled the same distance horizontally).
Friction force is (coeff. of friction)*(normal force), and the normal force is the same as the weight for a horizontal surface, which is (mass)*(grav. accel). If you work in reverse order of these steps, you should be able to find the work in J (which are the same as kg*m^2/s^2). Don't forget to add the friction forces for both masses. Hope this helps.

1. 👍
2. 👎
3. 👁
1. Nice question

1. 👍
2. 👎

## Similar Questions

1. ### Physics

1. The weight in the following diagram has a mass of 0.750 kg and the cart has a mass of 0.52 kg. There is a friction force of 2.1 N acting on the cart. What is the tension in the string? a. 4.4 N b. 4.3 N c. 4.1 N d. 4.2 N 2. An

2. ### physics

an experimental rocket plane lands on skids on a dry lake bed. it is traveling at 80.0 m/s when it touches down, how far does it slide before it comes to a stop? assume the coeffcient of kinetic friction between the skids and the

3. ### physics

Two boxes are connected by a weightless cord running over a very light frictionless pulley as shown in the figure. Box A, of mass 8.0 kg, is initially at rest on the top of the table. The coefficient of kinetic friction between

4. ### physics

1. The weight in the following diagram has a mass of 0.750 kg and the cart has a mass of 0.52 kg. There is a friction force of 2.1 N acting on the cart. What is the tension in the string? a. 4.4 N b. 4.3 N c. 4.1 N d. 4.2 N 2. An

1. ### Physics

The system shown in the ﬁgure is in equilibrium. A 15 kg mass is on the table. A string attached to the knot and the ceiling makes an angle of 54◦ with the horizontal. The coeﬃcient of the static friction between the 15 kg

2. ### physics

A 4 kg wooden block rest on a table. the coefficient of friction between the block and the table is .40. a 5kg mass is attached to the block by a horizontal string passed over a frictionless pulley of neglible mass what is the

3. ### physics

Masses 19 kg and 9 kg are connected by a light string that passes over a frictionless pulley as shown in the figure ( The figure shows the 19 kg block on the table connected by a string through a pulley which is connected to the 5

4. ### physic

A spring lies on a horizontal table, and the left end of the spring is attached to a wall. The other end is connected to a box. The box is pulled to the right, stretching the spring. Static friction exists between the box and the

1. ### physics

Two boxes are connected by a cord running over a pulley as shown in the picture below. Box I of mass 8.0 kg is on the top of the table; the coefficient of kinetic friction between box I and the table is 0.10. Box II has a mass of

2. ### physics homework 6

A damp washcloth is hung over the edge of a table to dry. Thus, part (mass = mon) of the washcloth rests on the table and part (mass = moff) does not. The coefficient of static friction between the table and the washcloth is

3. ### physics

The three blocks shown are released from rest and are observed to move with accelerations that have a magnitude of 1.5 m/s^2. Disregard any pulley mass or friction in the pulley and let M = 2 kg. The magnitude of the friction

4. ### physics

TWO BOXES A AND B ARE LYING ON THE TABLE AND ARE CONNECTED BY A PIECE OF STRING. THE MASS OF BOX A IS 3KG AND B IS 2KG. A 10N PULLING FORCE, POINTING TO THE RIGHT IS APPLIED TO BOX X CAUSING THE TWO BOXES TO MOVE TOGETHER AT