Answer:
0.657 seconds
Explanation:
speed of wave= wavelength / time period
so
time period= wavelength / speed
= 4.6/7
=0.657 sec
Answer:
Angular acceleration, is 
Explanation:
Given that,
Initial speed of the drill, 
After 4.28 s of constant angular acceleration it turns at a rate of 28940 rev/min, final angular speed, 
We need to find the drill’s angular acceleration. It is given by the rate of change of angular velocity.

So, the drill's angular acceleration is
.
Answer:
-75 cm
Explanation:
At l ; F = 350 Hz
At l + 15 cm ; F = 280 Hz
I = 350
I + 15 = 280
280I = 350(I + 15)
280I = 350I + 5250
280I - 350I = 5250
-70I = 5250
I = - 75cm
The length is - 75 cm
I haven't, but I'm sure @Porshia has!
Answer:
d. Imaginary point through which the resultant force of gravity acts on an object
Explanation:
Gravity acting on all particle points of the object, no matter how small they are. As a combination, the center of gravity would denote a single point which substitutes for all the gravity forces on the object.