A cricket ball of mass 0.4 kg moving with a velocity of 72 km/h is brought to rest by a player. Find the magnitude of the average force exerted by the player?
we have,
F= m x a to find acceleration we want either dist(s) or time(t)
it is not given how to find
they have given the answers as 40N how please help me
To find the magnitude of the average force exerted by the player, we need to use the equation F = m x a, where F is the force, m is the mass, and a is the acceleration.
First, we need to convert the velocity from km/h to m/s. We know that 1 km/h = 1000 m/3600 s = 5/18 m/s.
So the velocity of the cricket ball is (72 km/h) x (5/18 m/s) = 20 m/s.
Since the ball is brought to rest by the player, its final velocity is 0 m/s.
To find the acceleration, we can use the equation:
v^2 = u^2 + 2as
Here, v is the final velocity (0 m/s), u is the initial velocity (20 m/s), and s is the distance covered.
Rearranging the equation, we have:
s = (v^2 - u^2) / (2a)
Substituting the known values:
0 = (0 - (20^2)) / (2a)
Simplifying:
0 = - 400 / (2a)
Multiplying both sides by (2a):
0 = - 400
Since this equation does not have a solution, it means that the acceleration is undefined. Therefore, we cannot directly calculate the force exerted by the player using Newton's second law (F = m x a).
It is likely that the given answer of 40 N is incorrect or based on a different scenario.
To solve this problem, you need to use the equation F = m * a, where F is the force exerted, m is the mass of the ball, and a is the acceleration.
To find the acceleration, we can use the equation a = (v - u) / t, where v is the final velocity, u is the initial velocity, and t is the time taken.
In the given problem, the initial velocity (u) is 72 km/h, and the ball is brought to rest. This means that the final velocity (v) is 0 m/s.
First, let's convert the initial velocity from km/h to m/s:
72 km/h = 72 * (1000 m/3600 s) = 20 m/s
Now we can substitute the values into the equation:
a = (0 - 20) / t
However, we are not given either the time or the distance in this problem. This means that we cannot directly calculate the acceleration.
Now, since the ball comes to rest, we can assume that the average force exerted by the player is equal to the force required to bring the ball to rest. Therefore, the force exerted is equal to the product of the mass and acceleration.
Using the given mass of 0.4 kg, we have:
F = 0.4 kg * a
Since we don't have the exact value of acceleration, we cannot calculate the exact force exerted by the player using the given information.
The given answer of 40N may be incorrect or based on incorrect assumptions. Without additional information, we cannot determine the magnitude of the average force exerted by the player.
Force is change of momentum / time
= change in m v / t
You have to know the time