Explain why changes of state are physical change

Suppose a child drives a bumper car head on into the side rail, which exerts a force of 3400 N on the car for 0.400 s.

How is alternating current generated?

A wave has a speed of 50 m/s and a frequency of 100 Hz. Calculate its wavelength.

A man pulls a 50 kilogram box 20 meters across the floor with the aid of a rope tied to the box. The rope makes an angle of 30 degrees with the horizontal. In pulling the box the man exerts a force of 100 newtons. How much work is done by the man?

A mass spectrometer accelerates doubly ionized atoms of charge 2e over a potential difference V before they enter a uniform magnetic field B which is perpendicular to the direction of motion of the ions.

What happens to sound waves after they are received by our ears?

Which of the following chemical equations demonstrates that atoms are conserved during a chemical reaction?

How can an objects momentum be calculated

Give 10 examples of units you might use or see in any given day

What are three problems that can result from poor soil management? Erosion Nutrient depletion Development Desertification