KT Disney asked in Science & MathematicsPhysics · 1 month ago

# Physics problem?

An empty sled of mass 25 kg slides down a muddy hill with a constant speed of 2.4 m/s.

The slope of the hill is inclined at an angle of 15° with the horizontal as shown in the

figure above.

a. Calculate the time it takes the sled to go 21 m down the slope.

b. On the dot below that represents the sled, draw/label a free-body diagram for the sled

as it slides down the slope

c. Calculate the frictional force on the sled as it slides down the slope

Update:

the figure shown isn't needed to answer the question, it's just a free body diagram that's not needed to solve the problem.

Relevance
• 1 month ago

An empty sled of mass M = 25 kg slides down a muddy hill with a constant speed of V = 2.4 m/s.

The slope of the hill is inclined at an angle of theta = 15° with the horizontal as shown in the

figure above.

a. Calculate the time it takes the sled to go S = 21 m down the slope.

S = VT; so T = S/V = 21/2.4 = 8.75 seconds.  ANS

b. On the dot below that represents the sled, draw/label a free-body diagram for the sled as it slides down the slope  N/A.

c. Calculate the frictional force on the sled as it slides down the slope

The force down the slope is w = W sin(theta) as A = 0 acceleration we can write f = w - F = W sin(theta) - F = 0 since f = MA = M0 = 0.  That means the friction force F = W sin(theta) = Mg sin(theta) = 25*9.81*sin(radians(15)) = 63.5 N.  ANS.

• alex
Lv 7
1 month ago

Where's "as shown in the

figure above." ?