Recent content by sunnyday

I don't know how to do that.

Homework Statement A person jumps from the roof of a house 4.2-mhigh. When he strikes the ground below, he bends his knees so that his torso decelerates over an approximate distance of 0.66 m . If the mass of his torso (excluding legs) is 43 kg , find the magnitude of the average force exerted...

oh what. nvm. that was so weird. thank u so much!

Homework Statement Suppose the position of an object is given by r⃗ = (3.0t2i^ - 6.0t3j^)m. Where t in seconds. Determine r⃗ at time t = 2.5 s. Express your answer using two significant figures. Express your answer in terms of the unit vectors i^ and j^. Homework Equations plugging in 2.5...

When I divided 55/21, I got 2.619 (the same number as I got for seconds). I got 2 answers, the displacement for the ball (33.6109m) and the displacement for the stone (21.389m).

Homework Statement A ball is dropped from the top of a 55.0 m -high cliff. At the same time, a carefully aimed stone is thrown straight up from the bottom of the cliff with a speed of 21.0 m/s . The stone and ball collide part way up. How far above the base of the cliff does this happen...