What are electromagnetic waves? what are its characteristics? how do we classify them?

A tennis ball is thrown straight up with an initial speed of 20.5 m/s. It is caught at the same distance about ground as it is thrown.

Which of the following is an expressipn of velocity? O A. 55 mi north O B. 55 mph O C. 90 km O D. 90 km/h north

A cetain car weighs 25,000 N. Calculate the mass of the car. 245.000 kg 25,000 kg 9.81 m/s2 2,500 kg

Which of the following statements is true of a gas? It has a fixed volume, but not a fixed shape It has closely packed molecules It can change into a liquid by adding heat It takes the shape and size of a container

A football is kicked at an 50 degree angle to the horizontal, travels a horizontal distance of 20m before hitting the ground. what is the initial speed?

A person suffering from anaemia gets tired

Jessica took a Mylar balloon outside on a very hot day. As she waited for the bus the balloon began to get bigger. What is the best explanation of this?

Describe how electricity flows through a simple closed circuit.

Solar energy is produced by A. fusion of light nuclei to make heavier ones B. the slow release of heat left over from the Sun's formation C. fission of heavy nuclei into lighter ones D. solar magnetism

A 72-kg fisherman in a 114-kg boat throws a package of mass m = 15 kg horizontally toward the right with a speed of vi = 5.0 m/s.