What causes the different appearances of the moon?

Explain why action-reaction forces do not cancel each other out, resulting in zero net force.

What happens when you rub an ebonite stick with a wool cloth?

A 75.0 kg students sits 1.15 m away from a 68.4 kg student. What is the force of gravitational attraction between them? Give answer in scientific notation.

The mass of Jupiter is 1.9 * 1027 and that of the sun is 1.99 * 1030. The mean distance of Jupiter from the sun is 7.8 * 1011m. Calculate the gravitational force which the sun exerts on Jupiter, and the speed of Jupiter.

Analyze how buffers allow you to eat acidic and basic foods without changing your blood pH.

When you hear sound pulses (beats), describe how you will determine the beat frequency. Include in your answer what steps you will take to reduce percentage uncertainty, as well as how you will turn raw measurements into your final answer.

An elevator has mass 600 kg, not including passengers. the elevator is designed to ascend, at constant speed, a vertical distance of 20.0 m (five floors) in 16.0 s, and it is driven by a motor that can provide up to 40 hp to the elevator.

Suppose that 100g of aluminum at 23 degrees C is added to 50g of water at 95 degrees C. Determine the equilibrium temperature of the mixture. Ignore heat loss to the container or the surroundings.

Which property of coal makes it ideal for use in a power plant? Check all that apply. It burns easily. It makes ash. It is renewable. It produces a lot of energy. It contains mercury.

Bob is coming toward you at a speed of 75 km/hr. You throw a baseball in his direction at 75 km/hr. What does he see the ball doing?