Optics Answers

The antique projector has a 35 mm wide image at the center of the condenser lens. The focal length of the lens is 10 cm. Specifies the width of the image projected on the screen 10 m away from the projector lens.

a ship sails away from an iceberg. determine the temperature of the air if the distance of the ship from the iceberg is 846.3m after 2.6s V0°C=331.5m/s

eight seconds after a sound was emitted by a sonic altimeter, the echo is heard. How high is the airplane if the temperature is 10°C?

a lightning flash was seen 2 seconds before the clap of thunder. If the temperature was 25°C, how far away did the lightning occur

 An object is placed at the zero-mark of a meterstick while its image appears at the +15 cm mark using 

a convex mirror with a focal length of magnitude |𝑓𝑓| = 10 cm. Where is the mirror placed?

The surface of a lens is convex on one side, with a radius of curvature of 50

cm, and concave on the other side, with a radius of curvature of 15 cm. If it is made of a

certain plastic with a refractive index of 1.6, find the focal length of this lens.

Activity Title: Mechanical Energy

Learning Target : To determine the mechanical energy of a system. Consider a simple pendulum with a bob mass 4.2 kg

Questions:

1. If the speed of the bob at the lowest point B is 0.84 m/s , What is its kinetic energy at this point?

2. If points A and C are the highest points reached by the bob, What is the potential energy if h= 0.036m at these points.?

3. What is the kinetic energy of the bob points A and C ?

4. What is the potential energy at point B.?

5. What is the total mechanical energy at point A.?

6. What is the total mechanical energy at point B.?

A spring has constant of 875N/m. What hanging mass will cause this spring to stretch 4.5m ?

A hanging 7.5kg object stretches a spring 1.1 m What is the spring constant.?

A spring is stretched 0.75 m by using a force of 30N. What is the constant.?