Answer
Verified
105.9k+ views
Hint: As the ball changes its direction after striking the wall. So, we need to show the change in direction by a negative sign. Also, the velocity of the ball changes due to this, there must be a change in momentum which is equal to the force exerted by the wall.
Formula used:
The force is defined as the rate of change of linear momentum and written as:
\[F = \dfrac{{mv - mu}}{t}\]
Where m is the mass of an object
v is final velocity
u is initial velocity
t is time taken
Complete answer:
Given mass of a ball, m = 0.5 Kg
Final velocity of a ball, v = \[2m{s^{ - 1}}\]
Initial velocity of a ball, v = \[ - 2m{s^{ - 1}}\]( negative sign shows the direction of the velocity changes after striking the wall)
Time, t = 1 ms = \[{10^{ - 3}}\] sec
As we know that,
\[F = \dfrac{{mv - mu}}{t}\]
By using the given values, we get
\[F = \dfrac{{0.5 \times 2 - 0.5 \times ( - 2)}}{{{{10}^{ - 3}}}}\]
\[F = \dfrac{{1 + 1}}{{{{10}^{ - 3}}}}\]
\[F = 2 \times {10^3}\]
\[F = 2000{\rm{ N}}\]
Therefore, the average force exerted by the wall on the ball is 2000 N.
Hence option A is the correct answer
Note: From Newton’s second law of motion, force is equal to the time rate of change of momentum. By differentiating the momentum with respect to the time we can get the value for the force. The term momentum is defined as the product of mass and the velocity of an object.
Formula used:
The force is defined as the rate of change of linear momentum and written as:
\[F = \dfrac{{mv - mu}}{t}\]
Where m is the mass of an object
v is final velocity
u is initial velocity
t is time taken
Complete answer:
Given mass of a ball, m = 0.5 Kg
Final velocity of a ball, v = \[2m{s^{ - 1}}\]
Initial velocity of a ball, v = \[ - 2m{s^{ - 1}}\]( negative sign shows the direction of the velocity changes after striking the wall)
Time, t = 1 ms = \[{10^{ - 3}}\] sec
As we know that,
\[F = \dfrac{{mv - mu}}{t}\]
By using the given values, we get
\[F = \dfrac{{0.5 \times 2 - 0.5 \times ( - 2)}}{{{{10}^{ - 3}}}}\]
\[F = \dfrac{{1 + 1}}{{{{10}^{ - 3}}}}\]
\[F = 2 \times {10^3}\]
\[F = 2000{\rm{ N}}\]
Therefore, the average force exerted by the wall on the ball is 2000 N.
Hence option A is the correct answer
Note: From Newton’s second law of motion, force is equal to the time rate of change of momentum. By differentiating the momentum with respect to the time we can get the value for the force. The term momentum is defined as the product of mass and the velocity of an object.
Recently Updated Pages
Write a composition in approximately 450 500 words class 10 english JEE_Main
Arrange the sentences P Q R between S1 and S5 such class 10 english JEE_Main
Write an article on the need and importance of sports class 10 english JEE_Main
Name the scale on which the destructive energy of an class 11 physics JEE_Main
Choose the exact meaning of the given idiomphrase The class 9 english JEE_Main
Choose the one which best expresses the meaning of class 9 english JEE_Main