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

What happens if a hypothesis is not supported?

A person is jumping ...

Who discovered black hole radiation?

A man pushes on a piano of mass 180 kg so that it slides at a constant velocity down a ramp that is inclined at 11° above the horizontal. No appreciable friction is acting on the piano.

If a speed is based on what would be safe in wet weather, what would be the radius of curvature for a curve marked 40 km/h? the coefficient of static friction of rubber on wet concrete is μs=0.

An electron is located on the x axis at x0 = - 9.31*10-6 m. Find the magnitude and direction of the electric field at x = 9.39 * 10-6 m on the x axis due to this electron.

Earth attracts a person with a gravitational force of 7.0 * 102 newtons. What is the magnitude of the force with which the individual attracts Earth? 3.0 * 10² newtons 7.0 * 10² newtons 8.5 * 10² newtons 9.8 * 10² newtons

The productive cycle of a human is usually regulated by

Winston stands on the edge of a building's flat roof, 12 m above the ground, and throws a 147.0-g baseball straight down. the ball hits the ground at a speed of 18 m/s. what was the initial speed of the ball?

When is the zebra in motion when it is not moving