Please answer these two questions: A block is dropped onto a spring with k = 27
ID: 3894510 • Letter: P
Question
Please answer these two questions:
A block is dropped onto a spring with k = 27 N/m. The block has a speed of 3.2 m/s just before it strikes the spring. If the spring compresses an amount 0.10 m before bringing the block to rest, what is the mass of the block? Consider the skateboarder in the figure below. If she has a mass of 60 kg, an initial velocity of 24 m/s, and a velocity of 11 m/s at the top of the ramp, what is the work done by friction on the skateboarder? Ignore the kinetic energy of the skateboard's wheels.Explanation / Answer
a)1/2kx^2 = 1/2mv^2
m = k(x/v)^2
= 0.0264kg
b)W = -1/2m(vf2 - vi2)-mgh
= -1/2*60^(11^2-24^2)-60*9.8*5
= 10710J