Author Question: A uniform piece of wire, 20 cm long, is bent in a right angle in the center to give it an L-shape. ... (Read 72 times)

melina_rosy · **on:** Jul 29, 2018

A uniform piece of wire, 20 cm long, is bent in a right angle in the center to give it an L-shape. How far from the bend is the center of mass of the bent wire?

A) 2.5 cm
B) 3.5 cm
C) 4.5 cm
D) 5.0 cm
E) 7.1 cm

Question 2

A car approaches you at a constant speed, sounding its horn, and you hear a frequency of 76 Hz. After the car goes by, you hear a frequency of 65 Hz. What is the frequency of the sound emitted by the horn? The speed of sound in air is 343 m/s.

A) 68 Hz
B) 69 Hz
C) 70 Hz
D) 71 Hz
E) 72 Hz