Wednesday

March 4, 2015

March 4, 2015

Posted by **Sandhya** on Sunday, June 13, 2010 at 10:59pm.

(a) What is the coefficient of kinetic friction between the box and the surface of the incline?

(b) How much work is done on the box by the force of friction?

(c) What is the change in the potential energy of the box?

- physics -
**MathMate**, Monday, June 14, 2010 at 8:05am(a)

Distance, S = 9m

initial velocity, u = 0 m s^{-2}

final velocity, v = 2.4 m s^{-2}

acceleration, a (assumed uniform)

= (v²-u²)/2S

= (2.4²-0²)/(2*9)

= 0.32 ms^{-2}

Acceleration due to gravity, g

= 9.8 m s^{-2}

component of g along incline

= g sin(θ)

= 9.8 sin(15°)

= 2.536 m s^{-2}

Therefore reduced acceleration due to friction, af

= 2.536-0.32

= 2.216 ms^{-2}

Frictional force, F

= m(af)

= 25 kg * 2.216 m s^{-2}

= 55.411 N

Normal force acting on inclined plane, N

= m * g cos(θ)

= 25 * 9.8 * cos(15°)

= 236.6 N

Coefficient of kinetic friction, μ

= F/N = 0.234

(b) work done = force * distance

(c) Change in potential energy = mgh

where h is the difference in elevation (final - initial).

- physics -
**Anonymous**, Monday, June 14, 2010 at 8:41amif the mass were suspended by water and it's specific gravity were less than one would it knot float? slip up!

**Answer this Question**

**Related Questions**

Physics - A box is sliding up an incline that makes an angle of 13.0° with ...

Physics - A box is sliding up an incline that makes an angle of 12.0° with ...

Physics - A box is sliding up an incline that makes an angle of 17.0° with ...

physics help - I know that the answer to this problem is (0.2237232293) and to ...

Physics(Please help) - 1) A box is sliding up an incline that makes an angle of ...

11th grade - A box is sliding up an incline that makes an angle of 16.0° with ...

Physics - A box is sliding up an incline that makes an angle of 15.0 degrees ...

physics - You are a member of an alpine rescue team and must get a box of ...

Physics - A box starting from rest, slides down an incline which makes an angle ...

Physics - A box starting from rest, slides down an incline which makes an angle ...