6. According to a rule-of-thumb, every five seconds between a lightning flash and the following thunder gives the distance of the storm in miles. Assuming that the flash of light arrives in essentially no time at all, estimate the speed of sound in m/s from this rule.
lil_killer129Posts: 4,706Registered UserSenior Member
12. A bowling ball traveling with constant speed hits the pins at the end of a bowling lane 16.5 m long. The bowler hears the sound of the ball hitting the pins 2.5 s after the ball is released from his hands. What is the speed of the ball? The speed of sound is 340 m/s.
towerpumpkinPosts: 1,660Registered UserSenior Member
2.5=Ta+Tb, where Ta=time for ball to hit pins and Tb=time for sound of ball hitting to reach the bowler. d=vt, t=d/v, so Tb=16.5/340=.0485s. Ta=2.5-.0485=2.4515s. v=d/t=16.5/2.4515=6.73m/s
I hope this isn't homework that you haven't even attempted....
Calculate the average speed in m/s of a complete round-trip in which the outgoing 250 km is covered at 11.6 m/s followed by a 1.0-hour lunch break, and the return 250 km is covered at 17.2 m/s.
average speed = total distance / total time
time for outgoing 250 km = 250 x 10^3 m / (11.6 m/s) = 21 551 s = 5.986 h
time for break = 1 h
time for return 250 km = 250 x 10^3 m / (17.2 m/s) = 14 534 s = 4.037 h
total time = 11.02 h
Replies to: AP Physics Help!
I hope this isn't homework that you haven't even attempted....
how do u do this
time for outgoing 250 km = 250 x 10^3 m / (11.6 m/s) = 21 551 s = 5.986 h
time for break = 1 h
time for return 250 km = 250 x 10^3 m / (17.2 m/s) = 14 534 s = 4.037 h
total time = 11.02 h
total distance = 500 km
avg speed = 500/11.02 = 45.3 km/h = 12.6 m/s