00. Work done by Force and Power
Work, Energy and Power

148709 When a position dependent force $F=7-2 x+$ $3 x^{2} N$ acts on a small body of mass $2 \mathrm{~kg}$ and displaces it from $x=0$ to $x=5 \mathrm{~m}$, calculate the work done (in joules):

1 70
2 270
3 35
4 135
Work, Energy and Power

148710 A body is initially at rest. It undergoes onedimensional motion with constant acceleration. The power delivered to it at time $t$ is proportional to :

1 $\mathrm{t}^{1 / 2}$
2 $\mathrm{t}$
3 $t^{3 / 2}$
4 $\mathrm{t}^{2}$
Work, Energy and Power

148711 A uniform chain of mass $M$ and length $L$ is lying on a smooth horizontal table, with half of its length hanging down. The work done is pulling the entire chain up the table is

1 $\frac{\mathrm{MgL}}{2}$
2 $\frac{\mathrm{MgL}}{4}$
3 $\frac{\mathrm{MgL}}{8}$
4 $\frac{\mathrm{MgL}}{16}$
Work, Energy and Power

148712 A ball is moved along a straight line by a machine delivering constant power. The distance moved by the body in time $t$ is proportional to

1 $t^{1 / 2}$
2 $t^{3 / 4}$
3 $t^{3 / 2}$
4 $t^{2}$
Work, Energy and Power

148709 When a position dependent force $F=7-2 x+$ $3 x^{2} N$ acts on a small body of mass $2 \mathrm{~kg}$ and displaces it from $x=0$ to $x=5 \mathrm{~m}$, calculate the work done (in joules):

1 70
2 270
3 35
4 135
Work, Energy and Power

148710 A body is initially at rest. It undergoes onedimensional motion with constant acceleration. The power delivered to it at time $t$ is proportional to :

1 $\mathrm{t}^{1 / 2}$
2 $\mathrm{t}$
3 $t^{3 / 2}$
4 $\mathrm{t}^{2}$
Work, Energy and Power

148711 A uniform chain of mass $M$ and length $L$ is lying on a smooth horizontal table, with half of its length hanging down. The work done is pulling the entire chain up the table is

1 $\frac{\mathrm{MgL}}{2}$
2 $\frac{\mathrm{MgL}}{4}$
3 $\frac{\mathrm{MgL}}{8}$
4 $\frac{\mathrm{MgL}}{16}$
Work, Energy and Power

148712 A ball is moved along a straight line by a machine delivering constant power. The distance moved by the body in time $t$ is proportional to

1 $t^{1 / 2}$
2 $t^{3 / 4}$
3 $t^{3 / 2}$
4 $t^{2}$
Work, Energy and Power

148709 When a position dependent force $F=7-2 x+$ $3 x^{2} N$ acts on a small body of mass $2 \mathrm{~kg}$ and displaces it from $x=0$ to $x=5 \mathrm{~m}$, calculate the work done (in joules):

1 70
2 270
3 35
4 135
Work, Energy and Power

148710 A body is initially at rest. It undergoes onedimensional motion with constant acceleration. The power delivered to it at time $t$ is proportional to :

1 $\mathrm{t}^{1 / 2}$
2 $\mathrm{t}$
3 $t^{3 / 2}$
4 $\mathrm{t}^{2}$
Work, Energy and Power

148711 A uniform chain of mass $M$ and length $L$ is lying on a smooth horizontal table, with half of its length hanging down. The work done is pulling the entire chain up the table is

1 $\frac{\mathrm{MgL}}{2}$
2 $\frac{\mathrm{MgL}}{4}$
3 $\frac{\mathrm{MgL}}{8}$
4 $\frac{\mathrm{MgL}}{16}$
Work, Energy and Power

148712 A ball is moved along a straight line by a machine delivering constant power. The distance moved by the body in time $t$ is proportional to

1 $t^{1 / 2}$
2 $t^{3 / 4}$
3 $t^{3 / 2}$
4 $t^{2}$
Work, Energy and Power

148709 When a position dependent force $F=7-2 x+$ $3 x^{2} N$ acts on a small body of mass $2 \mathrm{~kg}$ and displaces it from $x=0$ to $x=5 \mathrm{~m}$, calculate the work done (in joules):

1 70
2 270
3 35
4 135
Work, Energy and Power

148710 A body is initially at rest. It undergoes onedimensional motion with constant acceleration. The power delivered to it at time $t$ is proportional to :

1 $\mathrm{t}^{1 / 2}$
2 $\mathrm{t}$
3 $t^{3 / 2}$
4 $\mathrm{t}^{2}$
Work, Energy and Power

148711 A uniform chain of mass $M$ and length $L$ is lying on a smooth horizontal table, with half of its length hanging down. The work done is pulling the entire chain up the table is

1 $\frac{\mathrm{MgL}}{2}$
2 $\frac{\mathrm{MgL}}{4}$
3 $\frac{\mathrm{MgL}}{8}$
4 $\frac{\mathrm{MgL}}{16}$
Work, Energy and Power

148712 A ball is moved along a straight line by a machine delivering constant power. The distance moved by the body in time $t$ is proportional to

1 $t^{1 / 2}$
2 $t^{3 / 4}$
3 $t^{3 / 2}$
4 $t^{2}$