Physics Answers

9. A 6.0 kg object (at rest) is released from a height of 80 m. If air resistance is negligible and g = 9.8 N/kg, the kinetic energy of the mass when it is 20 m above the ground is:

(a) 4.7 × 103 J (b) 3.5 × 103 J

(c) 2.4 × 103 J (d) 1.2 × 103 J

Cody car accelerates from 0m/s to 45m/s northward in 15 seconds. What is the acceleration of the car?

A 2 kg rectangular thin plate has a length of 0.5 m and a width of 0.20. the moment of inertia

of the plate is 0.29 kg-m2

. Where is the location of the axis of rotation?

a uniform sphere has a radius of 0.10 m. the moment of inertia of the sphere when axis

of rotation is located at its center is 0.08 kg-m2

, find the mass of the sphere.

A 9 kg solid cylinder has a radius 0.10m and thickness 5 cm. the axis of rotation is

located at the center of the cylinder. Compute for the moment of inertia.

What is the moment of inertial of a 3kg uniform rod with length 2 meters and radius

20cm, if the axis of rotation is located at (a) one end of the rod, (b) at the center of the

rod and (c) through the center?

How long (means time) must a 400 W electrical engine work in order to produce 300 kJ of work?

The force between a 100 kg man and the Earth is 980 N. How close must two protons (1.6 X 10^-19 C) be to generate the same force?

object traveling at 90% speed of light what would it appear as to observer from sending point ,the object ,and destination point, and from a 4th observation from 90% angle, 4th point is most important and observed effects of movement on spacetime from 4th point...

Two electrons are 10^-5 m apart. One electron is fixed on its position. The other, originally at rest, is released. How fast is the free electron moving when it is 10^−3 m from the fixed charge? Apply conservation of energy.