# Work energy

posted by .

Question Details
Three masses m1= 5.0 kg ; m2= 10.0 kg ; m1= 15.0 kg are attached by a strings over frictionless pulleys. The horizontal surface exerts a force of friction of 30N on m2. If the system is released from rest, use energy concepts to find the speed of m2 after it moves 4.0 meter

You need to describe the figure that goes with this. Are m1 and m3 hanging from pulleys at the ends of the horizontal surface? Is 15kg supposed to be m3? You call it m1.

The energy concepts you can use are to equate
Potential energy decrease = (frictional work done) + (kinetic energy increase).

The frictional work done is 30Nx4m = 120 J.
Get the new velocity V from the kinetic energy increase. I assume all three masses will have that velocity.

If one mass rises while another falls an amount X, the potential energy decrease will be (mass difference)* g * X

Sorry there was a mistake on my part

M1=5 kg
M2=10 kg
M3=15 kg

while m1 and m3 are hanging with a support of a pulley and M2 reside on the horizontal surface

• Work energy -

dgfdg

## Similar Questions

1. ### physics

Three blocks of masses M1=26kg,M2=38kg and M3=41kg are connected by 2 strings over 2 pulleys.Friction is negligible. 1. Determine the magnitude of acceleration and 2. the magnitude of the tension in each of two strings
2. ### Physics

A box of mass m2 = 3.1 kg rests on a frictionless horizontal shelf and is attached by strings to boxes of masses m1 = 1.6 kg and m3 = 2.6 kg as shown below. Both pulleys are frictionless and massless. The system is released from rest. …
3. ### Physics

Three objects with masses m1 = 7.4 kg, m2 = 11 kg, and m3 = 18 kg, respectively, are attached by strings over frictionless pulleys (M1 hangs off the left side of the table and M3 hangs off the right side of the table with M2 between …
4. ### Science

Three masses sitting on three pulleys,the masses are 5kg,9kg,8kg.the system is in equilibrium,the pulleys are frictionless & massless
5. ### Science

The system of three pulleys is in equilibrium, the pulleys have masses of 9kg ,5kg,8kg respectively. The pulleys are frictionless & massless.find the force T ?
6. ### Physics

3 objects with masses m1=5kg, m2=10kg and m3=15kg are attached by massless string over two frictionless pulleys. The horizontal surface is frictionless and system is released from rest. Using energy concept calculate m3 speed after …
7. ### physics

Note: The direction of the acceleration ~a of the system is given in the figure. Three masses (17 kg, 21 kg and 67 kg) are connected by strings. The 67 kg mass slides on a horizontal surface of a table top and the 17 kg and 21 kg masses …
8. ### physics

a block B (m2 = 14 kg) is at rest on top of a table. Block B is connected to block A (m1 = 4.8 kg) and block C (m3 = 17 kg) by two strings that each pass over a frictionless pulley installed at the either end of the table. The horizontal …
9. ### Physics

1. The figure shows a 100-kg block being released from rest from a height of 1.0 m. It then takes 0.53 s for it to reach the floor. What is the mass m of the block on the left?
10. ### Physics

1. The figure shows a 100-kg block being released from rest from a height of 1.0 m. It then takes 0.53 s for it to reach the floor. What is the mass m of the block on the left?

More Similar Questions