Physics Answers

A girl throws a ball vertically upward at 10m/s from a roof of a building 20m high.

(a) How long will it take the ball to reach the ground?

(b) What will it's velocity be just before it strikes the ground?

A concave mirror is positioned at a distance 5cm from an object. Give a linear magnification of F.If the image is upright calculate the radius curvature of the mirror

The critical angle for light traveling from a transparent medium to air is measured as 3F. The refractive index of the medium is

An object placed 12cm in front of a convex lens produced a virtual image of magnification 3.0. Calculate the focal length of the lens

A ball of mass 200g dropped from a height of 2m, hits the horizontal floor and rebound to a height h below it's initial position. If the coefficient of restitution is 0.8, calculate the value of h

An 80kg man is parachuting and experiencing a downward acceleration of

2.5m/s2 . The mass of the parachute is 5 kg.

(i) What is the value of the upward force exerted on the parachute by the air?

(ii) What is the value of the downward force exerted by the man on the parachute?

Calculate the force on the wire

shown in the figure, given B=1.50 T, L=5.00

cm, and I=20.0 A.

A bus is moving at 5.0 m/s when a passenger walks forward at 1.5 m/s relative to the bus. How fast is this passenger moving as seen and measured by (a) a person waiting at the bus stop and (b) the driver of the bus?

The life time of an atom on a metastable state is the order of 

a rocket is fired with an initial velocity of 100m/s at an angle of 50⁰above the horizontal .

it explodes on the mauntain side 12s after it is fring .what is the x-and y-coordinate of the rocket relative to its firing point?