How much force would you need to cause a 20 kilogram object to accelerate in a straight line

Which statement describes the magnetic field within a bar magnet?

What is the wave speed of a wave with a frequency of 100 Hz and a wavelength of 0.30 m?

You have been asked to design a "ballistic spring system" to measure the speed of bullets. A spring whose spring constant k is is suspended from the ceiling. A block of mass M hangs from the spring.

A uniform wire is cut into 4 segments. Each segment is twice as long as the earlier segment. If the shortest segment has a resistance of 4 ohm, find the resistance of original wire.

If the Earthwere twice as massive as it is now, then the gravitational force between it andthe Sun would be

Bus A and Bus B leave school on a field trip when a stopwatch reads zero. Bus A travels at a constant 50 km/h, and Bus B travels at a constant 75 km/h. How far are the two buses from school when the stopwatch reads 1.5 h?. a ... Bus A is 76.

When observed from Earth, the wavelengths of light emitted by a star are shifted toward the red end of the electromagnetic spectrum. Why does this redshift occur?

Object A has a length of 3 cm, a width of 10 cm, and a height of 2 cm. Object B is dropped into a graduated cylinder. It displaces 60 mL of water. The volume of object A is:

Is the following sentence true or false? Some information about an object or process may be missing from a model.

If V is a velocity, l a length, and v a fluid property having dimensions of L2T-1, which of the following combinations are qualitatively dimensionless (show work for a through d) : (a) V l v (b) Vl/v (c) V2v (d) V / (l v)