Choose the letter of the answer that best completes

the statement or answers the question.

1. If a vehicle increases its speed from 20 mph to 60

mph, its braking distance will increase by

a. 3 times.

b. 4 times

c. 9 times.

d. 40 times.

if the input force on a wheel and axle is 2 N and the output force is 20N what is its mechanical advantage

How long does it usually take a hypothesis to become a theory

Which statement is supported by Einstein's postulates of special relativity? The laws of physics change, depending on the state of motion of the observer. The laws of physics change, depending on the reference frame of the observer.

A hardworking ant must supply 0.00805 n to pull a small piece of fruit at constant velocity over a distance of 9.80 cm up a small hill to the entrance of the colony. if the coefficient of kinetic friction between the piece of fruit and the 15.

A 81 kg block is released at a 3.8 m height. the track is frictionless. the block travels down the track, hits a massless spring constant k=1888. calculate the average force

Ovens, toasters, dryers, and heat lamps are examples of inventions that convert electrical energy to thermal energy, which is a kind of kinetic energy.

Why does Alpha Centauri appear to be yellow-white?

In order to determine speed, you must know

Which of the statements best describes the relationship between the surface of an object and the amount of friction it produces? A.) The smoother the surface of an object, the more friction it will produce. B.

Laboratory measurements show hydrogen produces a spectral line at a wavelength of 486.1 nanometers (nm). A particular star's spectrum shows the same hydrogen line at a wavelength of 486.0 nm. What can we conclude