A simple model of the hydrogen atom suggests that the electron orbits the proton. What is the

force that keeps the electron in orbit?

A. Electrostatic

B. Gravitational

C. Strong nuclear

D. Centripetal

At a construction site, the site manager notices that a crane takes 20 seconds to lift a 500kg steel beam up to a height of 15 meters. From this information, he calculates the power output of the crane to be what value?

If R1 = 6 Ω, R2 = 8 Ω, R3 = 2 Ω, ε1 = 4 V, and ε2 = 14 V, what is the current in R

The first excited state of a particular atom in a gas is 5.7 eV above the ground state. A moving electron collides with one of these atoms, and excites the atom to its first excited state.

Two students start from opposite ends of an 8 km course walking towards each other. One student is walking at a rate of 4 km/h and the other is walking at a rate of 6 km/h. After how long will the students meet?

g The magnetic force on a charged particle A. depends on the sign of the charge on the particle. B. depends on the velocity of the particle. C. depends on the magnetic field at the particle's instantaneous position. D.

A baseball flying through the air has kinetic energy because of its motion. true or false?

How many poles does Jupiter's magnetosphere have? a. 2 c. 8 b. 4 d. 9

Which describes nuclear fusion? The nuclei of two atoms combine to form a larger nucleus. The nucleus of one atom splits to form two smaller nuclei. The electrons of two atoms combine to form a cluster of electrons.

In a class debate, a student argues that the big bang theory is "just a theory." What is most likely to be this student's understanding of scientific theories? A. Theories agree with observations of nature. B. Theories are just guesses. C.

Look at the advertisement. A poster that reads, "There's more to resistors than resistance. If you're really serious about cost, be serious about quality." with tools. Which persuasive media technique is used in this advertisement