Answer:
Average force = 3.5 kN
Explanation:
Given:
Mass of Jennifer (m) = 50 kg
Initial velocity = 35 m/s
Time taken to stop body = 0.5 s
Find:
Average force
Computation:
v = u + at
0 = 35 + a(0.5)
Acceleration (a) = - 70 m/s² = 70 m/s²
Average force = ma
Average force = (50(70)
Average force = 3500 N
Average force = 3.5 kN
Answers:
a) 
b) 
Explanation:
a) The centripetal acceleration
of an object moving in a uniform circular motion is given by the following equation:
Where:
is the angular velocity of the ball
is the radius of the circular motion, which is equal to the length of the string
Then:
This is the centripetal acceleration of the ball
b) On the other hand, in this circular motion there is a force (centripetal force
) that is directed towards the center and is equal to the tension (
) in the string:

Where
is the mass of the ball
Hence:

This is the tension in the string
Answer:
Explanation:
Let the intensity of unpolarised light be I₀ . After passing through the first polarising filter , the intensity is I₀ / 2 .
After second filter , the intensity will be I₀ / 2 x cos²45 = I₀ / 4
After third filter , the intensity will be I₀ / 4 x cos²45 = I₀ / 8 .
So,
1 / 8 the of initial light passes through the last filter .