# physics

posted by .

A force of 20 N is needed to overcome a frictional force if 5 N and accelerate a 3 kg mass across a floor. What is the acceleration of the mass?

• physics -

F = m a
F = 20-5 = 15N
so
15 = 3 a
a = 5 m/s^2

• physics -

a= 5m/^2

## Similar Questions

1. ### Physics, 4 short questions

VERY IMPORTANT FOR AN ESSAY ASSIGNMENT. PLEASE HELP ASAP! THANK U VERYYYYY MUCH! 1. What force is needed to give a mass of 25 kg an acceleration of 20m/s squared?
2. ### Mechanics

What force accelerates a 3kg mass at a rate of 4m/s^2?
3. ### Mechanics

A force of 25N causes an acceleration of 2m/s^2 when acting on a 7kg mass. What is the frictional force also acting?
4. ### math

How much force is needed to accelerate a 50-kg rider and her 250-kg motorcycle at 5 m/s2?
5. ### Physics

A horizontal force of 234 N causes a 350 N object to accelerate across a horizontal floor. if the coefficient of friction is 0.15, what is the value of the frictional force opposing the acceleration?
6. ### Physics

A person is pushing on a refrigerator that sits on a level floor. Use Newton's third law along with his second law to find the magnitude of the acceleration of a man as he pushes the refrigerator. Assume the man has a mass of 62 kg, …
7. ### Physics

A rope exerts a constant horizontal force of 203N pulling a 68-kg crate across the floor. The velocity of the crate is observed to increase from 3m/s to 5m/s in a time of 4 seconds under the influence of this force and the frictional …
8. ### physics : friction

a man pushes a packing case which has a total mass of 50 kg across a floor at a constant speed of 0.4 m s-1 by exerting a horizontal force of 100 N. (a) what was the resultant force on the case?
9. ### physics

A box of mass 10 kg is pushed across the floor with a force of 25 N. A 2 N frictional force opposes the motion. What is the acceleration of the box?
10. ### physics

How mush force must be exerted at an angle of 45 to top of a table to push along a weight when the frictional resistance to be overcome is a force of 2kg. Force is given in kg so i understand like this: N=kg.m/s^2 so the force in N …

More Similar Questions