Why electric potential of earth is taken to be zero?

An object travels along a right triangle with sides 3 m, 4 m, and 5 m. It returns back to the initial position.

Calculate the amount of heat (in kJ) required to convert 97.6 g of water to steam at 100° C. (The molar heat of vaporization of water is 40.79 kJ/mol.)

A car in front of the school goes from rest to 5.6 m/s in 3 seconds. What is its acceleration?

A ball is thrown straight up at an initial speed of 9.8m/s and, on returning to your hand, hits it moving downward at the same speed. If the whole trip took 2.0s, determine the ball's (a) average acceleration and (b) average velocity.

A hockey player makes a slap shot exerting a constant force of of 25.0 on the puck for. 16 seconds with the magnitude of the impulse given to the puck?

The potential difference between the terminal of an electrical heater is 60v when it draw a current 4A fron the source. What current will the heater draw if the potential difference is increased to 120v?

Which answer choice best explains why nuclear reactions release more energy than chemical reactions? Electrostatic forces of repulsion are thousands of times stronger than gravitational forces.

A train's mass is 18181.81 kg. What is its weight?

a 3.0m long frictionless pendulum swings with a maximum angluar displacement of 10 degree from the vertical. at its lowest position the kinetic energy of the pendulum is 20.0j what is the potential energy of the pendulum when the kientic energy is 5.

How are hypotheses and theories related to each other?