Answer:
D
A machine can help decrease the input force and increase the output force.
Okay, so they want to basically Increase their grip, and they are taking advantage of the force of friction
Answer:
1.)The field energy will increase.
The rest of the answers:
2.)The energy increases, and the lines of force are denser
3.) It points toward the field of earths magnetic poles.
4.) l, ll, and lll only
5.) ll, lV, l, lll
f' = frequency observed by the police car after sound reflected from the vehicle and comes back to police car = 1250 Hz
f = frequency emitted by the police car = 1200 Hz
V = speed of sound = 340 m/s
v = speed of vehicle = ?
frequency observed by the police car is given as
f' = f (V + v)/(V - v)
inserting the values in the above equation
1250 = 1200 (340 + v)/(340 - v)
v = 6.9 m/s
