The kinetic energy acquired by a mass m in travelling a certain distance d starting from rest under the action of a constant force is directly proportional to 

(1) m

(2) Independent of m

(3) 1/m

(4) m

Subtopic:  Concept of Work |
 63%
Level 2: 60%+
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An open knife edge of mass 'm' is dropped from a height 'h' on a wooden floor. If the blade penetrates upto the depth 'd' into the wood, the average resistance offered by the wood to the knife edge is 

(1) mg

(2) mg1−hd

(3) mg1+hd

(4) mg1+hd2

Subtopic:  Gravitational Potential Energy |
 60%
Level 2: 60%+
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A body is moving along a straight line by a machine delivering constant power. The distance moved by the body in time t is proportional to 

(1) t1/2

(2) t3/4

(3) t3/2

(4) t2

Subtopic:  Power |
 77%
Level 2: 60%+
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The relationship between force and position is shown in the given figure (in a one-dimensional case). The work done by the force in displacing a body from \(x = 1~\text{cm}\) to \(x = 5~\text{cm}\) is:
      
1. \(20~\text{ergs}\) 
2. \(60~\text{ergs}\)
3. \(70~\text{ergs}\) 
4. \(700~\text{ergs}\)

Subtopic:  Work Done by Variable Force |
 85%
Level 1: 80%+
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The graph shown represents the variation of extension (in cm) with load (in kg) for a spring balance. The spring constant of the spring is:

      

1. \(0.1\text{ N/cm}\)

2. \(5\text{ N/cm}\)

3. \(0.3\text{ N/cm}\)

4. \(1\text{ N/cm}\)

Subtopic:  Elastic Potential Energy |
Level 3: 35%-60%
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Adjacent figure shows the force-displacement graph of a moving body, the work done in displacing body from x = 0 to x = 35 m is equal to-

(1) 50 J

(2) 25 J

(3) 287.5 J

(4) 200 J

Subtopic:  Work Done by Variable Force |
 88%
Level 1: 80%+
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A 10kg mass moves along x-axis. Its acceleration as a function of its position is shown in the figure. What is the total work done on the mass by the force as the mass moves from x = 0 to x = 8 cm ?

(1) 8 × 10–2 joules

(2) 16 × 10–2 joules

(3) 4 × 10–4 joules

(4) 1.6 × 10–3 joules

Subtopic:  Work Done by Variable Force |
 71%
Level 2: 60%+
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A toy car of mass 5 kg moves up a ramp under the influence of force F plotted against displacement x. The maximum height attained is given by

1. ymax = 20 m

2. ymax = 15 m

3. ymax = 11 m

4. ymax = 5 m

Subtopic:  Gravitational Potential Energy |
 78%
Level 2: 60%+
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The graph between the resistive force \(F\) acting on a body and the distance covered by the body is shown in the figure. The mass of the body is \(25\) kg and the initial velocity is \(2\) m/s. When the distance covered by the body is \(4\) m, its kinetic energy would be:

   
1. \(50\) J
2. \(40\) J
3. \(20\) J
4. \(10\) J

Subtopic:  Work Done by Variable Force |
 56%
Level 3: 35%-60%
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A particle of mass 0.1 kg is subjected to a force which varies with distance as shown in fig. If it starts its journey from rest at x = 0 , its velocity at x = 12 m is 

(1) 0 m/s

(2) 202 m/s

(3) 203 m/s

(4) 40 m/s

Subtopic:  Work Done by Variable Force |
 74%
Level 2: 60%+
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