Physics Answers

An optical fiber whose core refractive index is 1.5 and refractive index of cladding is 1.47.Determine

1) the critical angle at the core cladding interface

2) the numerical aperture

3) the acceptance angle

An 85-kg runner is accelerating at a rate of 2 m/s^2 and a 65-kg runner at a rate of 3 m/s^2. If the heavier runner started at a speed of 1 m/s while the lighter runner started off stationary, then how long is it before the runners have the same momentum?

A 3500-kg car hits an 80-kg pedestrian who is standing in the middle of the road. Before the collision, the car was travelling at 30 km/h and the pedestrian was stationary. After the collision, the car was traveling at 28.5 km/h. At what speed will the pedestrian be flung down the road (in km/h)

Determine the length of guitar string required to produce a fundamental

frequency (1st harmonic) of 300 Hz. The speed of waves in a particular guitar string

is known to be 50 m/s.

Which of the following is NOT TRUE about X-rays? I

(A) Highly energetic collision can cause the inner

electrons to transit between high energy level and low

energy level.

(B) Hard X-rays could be used in deep tissue therapy.

(C) The penetration capability of X-rays can be

improved by the increase of the tube voltage.

(D) The X-rays from an X-ray tube are with a single

wavelength.

The radioactive nucleus of a given element does NOT

emit [ ].

(A) X-rays

(B) y-rays

• (C) a(alfa)particles

(D) B (beta)particles

I got this question on my hw and i chose 4 and it was wrong I would like if someone could explain why its wrong

A hockey stick hits a puck on the ice. Identify an action-reaction pair in this situation

1 The stick exerts a force on the puck; the puck exerts a force on the stick.

2 The puck exerts a force on the stick; the stick exerts a force on the ice.

3 The stick exerts a force on the ice; the ice exerts a force on the puck.

4 The stick exerts a force on the puck; the puck exerts a force on the ice.

45. The Solar Maximum Mission Satellite was placed in a circular orbit about 150 mi above Earth. Determine (a) the orbital speed of the satellite and (b) the time required for one complete revolution.

What do you think the role of communication company in the delivery of information

A particle of mass m is confined between 0<=x<=l. If px be the momentum, then find px in the ground state