Answer:
An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
Explanation:
When an athlete tries to stop his career, it takes several meters to stop completely, due to the inertia produced.
When trying to push a car, at first it is very difficult, because, due to inertia, the car tends to remain still. But once it is put into motion, the effort is much less to be done, since then inertia causes it to keep moving.
Solution :
Given weight of Kathy = 82 kg
Her speed before striking the water,
= 5.50 m/s
Her speed after entering the water,
= 1.1 m/s
Time = 1.65 s
Using equation of impulse,

Here, F = the force ,
dT = time interval over which the force is applied for
= 1.65 s
dP = change in momentum
dP = m x dV
![$= m \times [V_f - V_o] $](https://tex.z-dn.net/?f=%24%3D%20m%20%5Ctimes%20%5BV_f%20-%20V_o%5D%20%24)
= 82 x (1.1 - 5.5)
= -360 kg
∴ the net force acting will be


= 218 N
Answer:
Sound wave is a longitudinal wave that propagates in a medium
Explanation:
<em>Part A:</em> (C) Sound wave is propagation of pressure fluctuations in a medium.
<em>Part B: </em>(C) Pressure fluctuations travel along the direction of propagation of the sound wave.
<em>Part C: </em>(A) Yes air play a role in the propagation of the human voice from one end of the lecture hall to the other.