Physics · Nuclear Physics
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The question is as follows:

- A
1250 J
- B
l000J
- C
3500J
- D
2500 J
This question requires use of calculus, and is beyond the scope of the pre-medical syllabus.
this option is incorrect. Work-Energy Theorem: The work done by the net force is equal to the change in kinetic energy.
* Kinetic Energy: KE = (1/2) * m * v^2, where m is mass and v is velocity.
* Initial Velocity (x=4m): v1 = 10 * √4 = 20 m/s
* Final Velocity (x=9m): v2 = 10 * √9 = 30 m/s
* Initial KE: KE1 = (1/2) * 10 * (20)^2 = 2000 J
* Final KE: KE2 = (1/2) * 10 * (30)^2 = 4500 J
* Work Done: W = KE2 - KE1 = 4500 J - 2000 J = 2500 J
this option is incorrect. Work-Energy Theorem: The work done by the net force is equal to the change in kinetic energy.
* Kinetic Energy: KE = (1/2) * m * v^2, where m is mass and v is velocity.
* Initial Velocity (x=4m): v1 = 10 * √4 = 20 m/s
* Final Velocity (x=9m): v2 = 10 * √9 = 30 m/s
* Initial KE: KE1 = (1/2) * 10 * (20)^2 = 2000 J
* Final KE: KE2 = (1/2) * 10 * (30)^2 = 4500 J
* Work Done: W = KE2 - KE1 = 4500 J - 2000 J = 2500 J
this option is incorrect.Work-Energy Theorem: The work done by the net force is equal to the change in kinetic energy.
* Kinetic Energy: KE = (1/2) * m * v^2, where m is mass and v is velocity.
* Initial Velocity (x=4m): v1 = 10 * √4 = 20 m/s
* Final Velocity (x=9m): v2 = 10 * √9 = 30 m/s
* Initial KE: KE1 = (1/2) * 10 * (20)^2 = 2000 J
* Final KE: KE2 = (1/2) * 10 * (30)^2 = 4500 J
* Work Done: W = KE2 - KE1 = 4500 J - 2000 J = 2500 J
the correct option is D.Work-Energy Theorem: The work done by the net force is equal to the change in kinetic energy.
* Kinetic Energy: KE = (1/2) * m * v^2, where m is mass and v is velocity.
* Initial Velocity (x=4m): v1 = 10 * √4 = 20 m/s
* Final Velocity (x=9m): v2 = 10 * √9 = 30 m/s
* Initial KE: KE1 = (1/2) * 10 * (20)^2 = 2000 J
* Final KE: KE2 = (1/2) * 10 * (30)^2 = 4500 J
* Work Done: W = KE2 - KE1 = 4500 J - 2000 J = 2500 J
Tagged under Physics · Nuclear Physics · 2021