What is the mass number of a potassium atom that has 20 neutrons

Which is physical change? A) Burning Wood B) Rusting metal C) Cooking an egg D) Freezing water

If the resistance force is 40 Newtons and the effort force is 20 Newtons, what is the mechanical advantage?

A person is pulling a freight cart with a force of 58 pounds. how much work is done in moving the cart 70 feet if the cart's handle makes an angle of 27° with the ground? round your answer to the nearest tenth.

A physics professor claims in court that the reason he went through the red light (λ = 660 nm) was that, due to his motion, the red color was Doppler shifted to green (λ = 510 nm). How fast was he going?

A 20 newton force moves an object southeast. What two properties of force have been described? A. magnitude and position B. direction and mass C. direction and magnitude D. magnitude and displacement

Photosynthesis is an endothermic chemical reaction that forms sugars from carbon dioxide, water, and the sun's energy. Which of the following must be true of photosynthesis?

What is a calorimeter used to measure?

When the mover pushes the box, two equal forces result. Explain why the box moves

What equation expresses the the work-energy theorem?

What is the potential energy for and object with mass of 15 Kg and 20 m above the ground?