A ball is thrown horizontally from a cliff and hits the ground 4 seconds later 40 meters from the base of the cliff. How high was the cliff (rounded to the nearest tenth of a meter) ?

A proton moves in a region of constant electric field. Does it follow that the proton's velocity is parallel to the electric field? Does it follow that the proton's acceleration is parallel to the electric field? Explain.

An EM wave has frequency 9.90*10^14 Hz. What is its wavelength? How would we classify it?

A cylinder with a valve at the bottom contains an ideal gas. The valve is opened and some of the gas escapes slowly. The valve is then closed, after which the piston is observed to be at a lower position.

A campfire is an example of an exothermic reaction. answer true or false

In water jet cutting and abrasive water jet cutting, the separation between the nozzle opening and the work surface is called which one of the following: (a) gap, (b) gap size, (c) orifice, (d) overcut, or (e) standoff distance?

What does Kepler's second law state? A. Planets travel in ellipses. B. Planets sweep equal areas in equal times. C. A planet's apparent backward movement is termed retrograde motion. D.

Why do charges build up in a cloud

How does the wave model of electrons orbiting the nucleus account for discrete energy values?

An ecosystem is all the populations of organisms that live together and A. the microorganisms that depend on them. B. the organisms that generate energy from sunlight. C. the physical factors with which they interact. D.

Which statement about magnetic poles is accurate? A) Same magnetic poles attract, while different magnetic poles repel. B) Same magnetic poles attract, while different magnetic poles attract.