An element's atomic number is 39. How many protons would an atom of this element have?

You throw a ball straight upward. As it leaves your hand, its speed is 15 m/s. (a) How much time does it take for the ball to reach the top of its trajectory? Start from a fundamental principle and show all your work.

Which of following is measured based on the pull of gravity a. distance b. speed c. mass d. weight

When fossil fuels are burned, they produce?, the main greenhouse gas responsible for global warming trends?

The scientific method is

A student exerts a force of 500 n pushing a box 10 m across the floor in 4 s. how much work does the student perform?

Lisa has three classes that each last 50 minutes qhat ia the total nuber of minutes of minutes of the three classe?

Which has a greater speed a heron hat travels 600m in 60 seconds or a duck that travels 60 m in 5 seconds? Explain

A machine shovel moves dirt at the rate of 1,100 pounds of dirt 1 foot in 1 second. How many horsepower is this?

Two descriptions about physical quantities are given below: Quantity A: It is a force. Quantity B: It changes when the object travels from Earth to Earth's moon. What quantities are these most likely describing? A.

How does the tilt of Earth's axis affect how the sun's rays strike Earth?