<u>Given that</u>
time (t) = 10 s ,
(S) = ?
We know that S = ut+ 1/2 a.t² m
since free fall and no air friction,
a = g = 9.81 m/s² ; initial velocity u= 0
S = 0 + [1/2 × 9.81 ×10²]
<em> S = 490.5 m </em>
The change in mechanical energy caused by the dissipative resistance force is equal to, difference between the potential energy and kinetic energy of the object.
Potential energy of the object, P.E = mgh
m is mass of the object = 10 kg
g is acceleration due to gravity = 9.8 m/s²
h= height from which it is dropped =50 m
Substituting the value we get,
P.E = 10×9.8×50 = 4900 J
Kinetic energy of the object, K.E = 
v is the velocity of the object = 26 m/s²
K.E = (1/2)×10×(26)²
= 3380 J
Change in mechanical energy caused by dissipative force = P.E ₋ K.E
= 4900 ₋ 3380 = 1520 J
It’s red shift and blue shift because This only occurs when the frequency of the wave is made longer or shorter due to the movement of the source relative to the observer
Answer:
They have mass is always true.