A force of 5 N making an angle θ with the horizontal acting on an object displaces it by 0.4 m along the horizontal direction. If the object gains kinetic energy of 1 J then the component of the force is:

1. 1.5 N 2. 2.5 N
3. 3.5 N 4. 4.5 N

Subtopic:  Work Energy Theorem |
 88%
Level 1: 80%+
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A pump ejects \(12,000~\text{kg}\) of water at a speed of \(4~\text{m/s}\) in \(40~\text{s}.\) The average rate at which the pump is working is:
1. \(0.24~\text{kW}\)
2. \(2.4~\text{W}\)
3. \(2.4~\text{kW}\)
4. \(24~\text{W}\)

Subtopic:  Power |
 79%
Level 2: 60%+
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A block of mass \(2~\text{kg}\) moving with a velocity of \(10~\text{m/s}\) on a smooth surface hits a spring of force constant \(80\times10^3~\text{N/m}\) as shown in the figure. The maximum compression in the spring will be:
               
1. \(5~\text{cm}\) 
2. \(10~\text{cm}\)
3. \(15~\text{cm}\)
4. \(20~\text{cm}\)

Subtopic:  Elastic Potential Energy |
 83%
Level 1: 80%+
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A body is displaced from \((0,0)\) to \((1~\text{m}, 1~\text{m})\) along the path \(x=y\) by a force \(F = (x^2\hat j+y\hat i)~\text{N}.\) The work done by this force will be:
1. \(\frac{4}{3}~\text{J}\)
2. \(\frac{5}{6}~\text{J}\)
3. \(\frac{3}{2}~\text{J}\)
4. \(\frac{7}{5}~\text{J}\)

Subtopic:  Work Done by Variable Force |
 79%
Level 2: 60%+
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A block of mass \(m\) initially at rest, is dropped from a height \(h\) onto a spring of force constant \(k.\) If the maximum compression in the spring is \(x,\) then:     
            
1. \(m g h = \frac{1}{2} k x^{2}\)
2. \(m g \left(h + x\right) = \frac{1}{2} k x^{2}\)
3. \(m g h = \frac{1}{2} k \left(x + h\right)^{2}\)
4. \(m g \left(h + x \right) = \frac{1}{2} k \left(x + h \right)^{2}\)

Subtopic:  Elastic Potential Energy |
 80%
Level 1: 80%+
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When a body moves non-uniformly on a circular path:
1. no work is done by the tangential force.
2. no work is done by the centripetal force.
3. work done by the tangential force is always positive.
4. work done by the centripetal force is negative.
Subtopic:  Work Done by Variable Force |
 72%
Level 2: 60%+
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What is the work done by the gravitational force on block \(A\) during the first \(2\) s after the blocks are released? (assume the pulley is light)

               

1. \( 240 ~\text J\)
2. \( 200 ~\text J\)

3. \(120 ~\text J\)

4. \( 24 ~\text J\)

Subtopic:  Gravitational Potential Energy |
 66%
Level 2: 60%+
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A weight 'mg' is suspended from a spring. The energy stored in the spring is U. The elongation in the spring is:

1.  2Umg

2.  Umg

3.  2Umg

4.  U2mg

Subtopic:  Elastic Potential Energy |
 65%
Level 2: 60%+
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In the given figure, a man pulls the mass \(m\) with the help of a rope. The work done by the man against gravity when mass is lifted by \(0.5~\text{m}\) is
\(\left(g= 10~\text{m/s}^2 \right)\)

      
1. \(50~\text{J}\)
2. \(100~\text{J}\)
3. \(25~\text{J}\)
4. Zero

Subtopic:  Elastic Potential Energy |
 66%
Level 2: 60%+
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A block is carried slowly up an inclined plane. If \(W_f\) is work done by the friction, \(W_N\) is work done by the reaction force, \(W_g\) is work done by the gravitational force, and \(W_{ex}\) is the work done by an external force, then choose the correct relation(s):
1. \(W _N +   W _f   +   W _g   +   W _{ex}   =   0\)
2. \(W _N   =   0\)
3. \(   W _f   +   W _{ex}   =    - W _g\)
4. All of these

Subtopic:  Work Energy Theorem |
 72%
Level 2: 60%+
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