Questions from College Physics

Q: A statue is 6.6 m from the opening of a

A statue is 6.6 m from the opening of a pinhole camera, and the screen is 2.8 m from the pinhole. (a) Is the image erect or inverted? (b) What is the magnification of the image? (c) To get a brighte...

Q: The peak force on a runner’s foot during a race is found

The peak force on a runner’s foot during a race is found to be vertical and three times his weight. What is the peak force on the foot of a runner whose mass is 85 kg?

Q: Esperanza uses a camera with a lens of focal length 50.

Esperanza uses a camera with a lens of focal length 50.0 mm to take a photo of her son Carlos, who is 1.2 m tall and standing 3.0 m away. (a) What must be the distance between the lens and the camera'...

Q: A person on a safari wants to take a photograph of a

A person on a safari wants to take a photograph of a hippopotamus from a distance of 75.0 m. The animal is 4.00 m long, and its image is to be 1.20 cm long on the camera's image sensor. (a) What foca...

Q: If the distance from the lens to the retina is 2.

If the distance from the lens to the retina is 2.00 cm, show that the focal length of the lens must vary between 1.85 cm and 2.00 cm to see objects from 25.0 cm to infinity.

Q: Use the result of Problem 58 to show that in any elastic

Use the result of Problem 58 to show that in any elastic head-on collision between two objects, the relative speed of the two is the same before and after the collision. [Hint: Look at the collision i...

Q: (a) What is the resistance of the heater element in

(a) What is the resistance of the heater element in a 1500 W hair dryer that plugs into a 120 V outlet? (b) What is the current through the hair dryer when it is turned on? (c) At a cost of $0.10 pe...

Q: The distance from the lens of a particular eye to the retina

The distance from the lens of a particular eye to the retina is 1.75 cm. What is the focal length of the lens when the eye produces a clear image of an object 25.0 cm away?

Q: A 35.0 nC charge is placed at the origin and

A 35.0 nC charge is placed at the origin and a 55.0 nC charge is placed on the +x-axis, 2.20 cm from the origin. (a) What is the electric potential at a point halfway between these two objects? (b)...

Q: One can estimate the size of the blind spot on the retina

One can estimate the size of the blind spot on the retina by treating the eye as a camera obscura. Suppose your friend Julie's eye can be approximated as a sphere of diameter 2.5 cm. She notices that...