At the start of his race, an 81-kg runner pushes against the starting block, exerting an average force of 1600 n . the force that the block exerts on his foot points 20∘ above the horizontal. determine the horizontal speed of the runner after the force is exerted for 0.28 s.

The motor m applies a time-varying force of f (200 t) n, where t is in seconds. box b with mass 200 kg starts from rest, and the coefficients of kinetic and static friction are 0.2 and us 0.3 the acceleration due to gravity is g 9.8 m/s2 b 300 a) find the time ' when the box starts to move. b) calculate the speed of the crate at 3 s c) calculate the power delivered by the motor at t 3 s

What is the most useful equation for electric power?

which statements describe the image? check all that apply. the wood is releasing argon gas. this information is useful for dating ancient rock. the process works only with organic matter. the element has a half-life of 5,730 years. this shows the half-life of carbon-19.