A weightlifter lifts a 125-kg barbell straight up 1.15 m in 2.5 s. What was the power expended by the weightlifter?

A student weighs a sample of sugar and records the measurement. He then writes down his his observations on the appearance of the sugar describing it as a white crystalline solid.

A freight train rolls along a track with considerable momentum. If it rolls at the same speed but hastwice as much mass, its momentum isa. zero. b. doubled. c. quadrupled. d. unchanged.

A 54-kg jogger is running at a rate of 3m/s. What is the kinetic energy f the jogger

The difference between scalar and vector

Which electromagnetic radiation can be seen with the human eye

What is the oxidation state of a hydrogen atom bound to an iron atom.?

What evidence can you present for the possibility of time travel?

A ball is being rolled by a normal push of 1000N. it is opposed by friction which has a force of 0.3kN and air resistance which has a force of 23N. Calculate the resultant force.

What was the change in internal energy (chemical energy plus thermal energy) of the person pulling the block?

One of the longer sides of a kite is 39 feet. one of the shorter sides is 25 feet. half the length of the shorter diagonal is 15 feet. what is the area of the kite?