Answer:
Explanation:
initial velocity u = 0
final velocity v = 11.3 m /s
distance covered s = 12.8 m
v² = u² + 2 a s
11.3² = 0 + 2 x a x 12.8
a = 4.99 m /s²
again ,
v = u + a t
11.3 = 0 + 4.99 t
t = 2.26 s .
Rest of the sprint will be covered with uniform velocity .
Distance covered = 100 - 12.8 = 87.2 m
speed = 11.3 m /s
time taken = 87.2 / 11.3 = 7.7 s
Total time of 100 m sprint = 7.7 + 2.26 = 9.96 m .
b )
Let the time taken to reach the top speed be t .
acceleration a = 11.3 / t
distance covered s = 1/2 a t²
= .5 x (11.3 / t) x t²
= 5.65 t
Rest of the distance = 100 - 5.65 t
time taken to cover rest of the distance = (100 - 5.65 t ) / 11.3
Total time = (100 - 5.65 t / 11.3 ) + t = 9.75
100 - 5.65 t + 11.3 t = 11.3 x 9.75
100 + 5.65 t = 110.175
5.65 t = 10.175
t = 1.8
acceleration a = 11.3 / t
= 11.3 / 1.8
= 6.278 m /s²
distance covered in 1.8 s
s = 1/2 a t²
= .5 x 6.278 x 1.8²
= 10.17 m .
The greater mass the object has the greater its inertia would be. As inertia becomes greater, the same happens with the force which is needed stop motion. Linear motion and rotational motion are quite different, because the first one depends only on mass while the second embraces mass, size and shape of an object. According to the information I shared, one will not be able to stop 10 kg mass due to far greater inertia than object of 1kg mass.
Hope you will find it helpful.
Option (B) is correct.The magnetic field strength=8.5 x 10² T
Explanation:
the magnetic force Fm is given by
Fm= q V B sinθ
q= charge=1.4 x 10⁻⁷ C
v= velocity= 1.3 x 10⁶ m/s
B= magnetic field strength
Fm= magnetic force= 1.5 x 10² N
θ=75°
so 1.5 x 10²=(1.4 x 10⁻⁷) (1.3 x 10⁶ ) (B) sin75
B=8.5 x 10² T
Its a solar cell. Photo voltaic Cell is also known as a solar cell.
