Answer:
1. (c) 600
2. (b) 3.6 J
Step-by-step explanation:
1. The total work done by the man when he lands is 588 J. This value is obtained by considering the work done against gravity during the vertical jump and the work done by the horizontal motion of the platform.
The work done against gravity is calculated by multiplying the weight of the man (60 kg) by the acceleration due to gravity (9.8 m/s^2) and the vertical distance jumped (1 m). This results in a value of 588 J.
On the other hand, the work done by the horizontal motion of the platform is zero. Since the man is at rest and there is no horizontal force acting on him, no work is done in this direction.
Therefore, The total work done by the man when he lands is approximately 588 J. The closest option provided is 600 J.
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2. Length of the chain = 2 m
Length of the hanging portion = 60 cm = 0.6 m
Total mass of the chain = 4 kg
First, let's calculate the mass of the hanging portion of the chain. We can use the ratio of lengths to find the proportionate mass.
Mass of hanging portion = (length of hanging portion / total length) * total mass
Mass of hanging portion = (0.6 m / 2 m) * 4 kg
Mass of hanging portion = 0.6 kg
Next, we can calculate the gravitational potential energy of the hanging portion of the chain.
Potential energy = mass * gravitational acceleration * height
Potential energy = 0.6 kg * 9.8 m/s^2 * 0.6 m
Potential energy = 3.528 J
The work done in pulling the entire chain onto the table is equal to the gravitational potential energy of the hanging portion of the chain.
Therefore, the correct answer is approximately 3.528 J. The closest option provided is (b) 3.6 J.