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

148718 A force $\vec{F}=(5 \hat{i}+4 \hat{j}) N$ acts on a body and produces a displacement $\overrightarrow{\mathrm{S}}=(6 \hat{\mathbf{i}}-5 \hat{\mathbf{j}}+3 \hat{\mathbf{k}}) \mathrm{m}$. The work done by the force is

1 $10 \mathrm{~J}$
2 $20 \mathrm{~J}$
3 $30 \mathrm{~J}$
4 $40 \mathrm{~J}$
Work, Energy and Power

148719 The heart of a man pumps $5 \mathrm{~L}$ of blood through the arteries per minute at a pressure of $150 \mathrm{~mm}$ of mercury. If the density of mercury be $13.6 \times 10^{3} \mathrm{~kg} / \mathrm{m}^{3}$ and $\mathrm{g}=10 \mathrm{~m} / \mathrm{s}^{2}$, then the power of heart in watt is

1 1.70
2 2.35
3 3.0
4 1.50
Work, Energy and Power

148720 The work done on the particle of mass $M$ by a force, is given as
$\mathbf{k}\left[\frac{\mathbf{x}}{\left(\mathrm{x}^{2}+\mathbf{y}^{2}\right)^{3 / 2}} \hat{\mathbf{i}}+\frac{\mathbf{y}}{\left(\mathrm{x}^{2}+\mathbf{y}^{2}\right)^{3 / 2}} \hat{\mathbf{j}}\right]$
( $k$ being constant of appropriate dimensions). When the particle is taken from the point $(\mathrm{a}, 0)$ to the point $(0$, a) along a circular path of radius a about the origin in the $x-y$ plane is

1 $2 \mathrm{k} \frac{\pi}{\mathrm{a}}$
2 $\mathrm{k} \frac{\pi}{\mathrm{a}}$
3 $\mathrm{k} \frac{\pi}{2 \mathrm{a}}$
4 0
Work, Energy and Power

148721 An elevator can carry a maximum load of 1000 $\mathrm{kg}$ is moving up with a constant speed of $2 \mathrm{~m} / \mathrm{s}$. The frictional force opposing the motion is $2000 \mathrm{~N}$. The minimum power delivered by the motor to the elevator is: (Assuming g=10 m/ $/ \mathrm{s}^{2}$ )

1 $18 \mathrm{~kW}$
2 $24 \mathrm{~kW}$
3 $20 \mathrm{~kW}$
4 $26 \mathrm{~kW}$
Work, Energy and Power

148722 A force $F=3 x^{2}+2 x+1$ acts on a body in the $x$ - direction. The work done by this force during a displacement from $x=-1$ to +1 is

1 2 units
2 4 units
3 6 units
4 8 units
Work, Energy and Power

148718 A force $\vec{F}=(5 \hat{i}+4 \hat{j}) N$ acts on a body and produces a displacement $\overrightarrow{\mathrm{S}}=(6 \hat{\mathbf{i}}-5 \hat{\mathbf{j}}+3 \hat{\mathbf{k}}) \mathrm{m}$. The work done by the force is

1 $10 \mathrm{~J}$
2 $20 \mathrm{~J}$
3 $30 \mathrm{~J}$
4 $40 \mathrm{~J}$
Work, Energy and Power

148719 The heart of a man pumps $5 \mathrm{~L}$ of blood through the arteries per minute at a pressure of $150 \mathrm{~mm}$ of mercury. If the density of mercury be $13.6 \times 10^{3} \mathrm{~kg} / \mathrm{m}^{3}$ and $\mathrm{g}=10 \mathrm{~m} / \mathrm{s}^{2}$, then the power of heart in watt is

1 1.70
2 2.35
3 3.0
4 1.50
Work, Energy and Power

148720 The work done on the particle of mass $M$ by a force, is given as
$\mathbf{k}\left[\frac{\mathbf{x}}{\left(\mathrm{x}^{2}+\mathbf{y}^{2}\right)^{3 / 2}} \hat{\mathbf{i}}+\frac{\mathbf{y}}{\left(\mathrm{x}^{2}+\mathbf{y}^{2}\right)^{3 / 2}} \hat{\mathbf{j}}\right]$
( $k$ being constant of appropriate dimensions). When the particle is taken from the point $(\mathrm{a}, 0)$ to the point $(0$, a) along a circular path of radius a about the origin in the $x-y$ plane is

1 $2 \mathrm{k} \frac{\pi}{\mathrm{a}}$
2 $\mathrm{k} \frac{\pi}{\mathrm{a}}$
3 $\mathrm{k} \frac{\pi}{2 \mathrm{a}}$
4 0
Work, Energy and Power

148721 An elevator can carry a maximum load of 1000 $\mathrm{kg}$ is moving up with a constant speed of $2 \mathrm{~m} / \mathrm{s}$. The frictional force opposing the motion is $2000 \mathrm{~N}$. The minimum power delivered by the motor to the elevator is: (Assuming g=10 m/ $/ \mathrm{s}^{2}$ )

1 $18 \mathrm{~kW}$
2 $24 \mathrm{~kW}$
3 $20 \mathrm{~kW}$
4 $26 \mathrm{~kW}$
Work, Energy and Power

148722 A force $F=3 x^{2}+2 x+1$ acts on a body in the $x$ - direction. The work done by this force during a displacement from $x=-1$ to +1 is

1 2 units
2 4 units
3 6 units
4 8 units
NEET Test Series from KOTA - 10 Papers In MS WORD WhatsApp Here
Work, Energy and Power

148718 A force $\vec{F}=(5 \hat{i}+4 \hat{j}) N$ acts on a body and produces a displacement $\overrightarrow{\mathrm{S}}=(6 \hat{\mathbf{i}}-5 \hat{\mathbf{j}}+3 \hat{\mathbf{k}}) \mathrm{m}$. The work done by the force is

1 $10 \mathrm{~J}$
2 $20 \mathrm{~J}$
3 $30 \mathrm{~J}$
4 $40 \mathrm{~J}$
Work, Energy and Power

148719 The heart of a man pumps $5 \mathrm{~L}$ of blood through the arteries per minute at a pressure of $150 \mathrm{~mm}$ of mercury. If the density of mercury be $13.6 \times 10^{3} \mathrm{~kg} / \mathrm{m}^{3}$ and $\mathrm{g}=10 \mathrm{~m} / \mathrm{s}^{2}$, then the power of heart in watt is

1 1.70
2 2.35
3 3.0
4 1.50
Work, Energy and Power

148720 The work done on the particle of mass $M$ by a force, is given as
$\mathbf{k}\left[\frac{\mathbf{x}}{\left(\mathrm{x}^{2}+\mathbf{y}^{2}\right)^{3 / 2}} \hat{\mathbf{i}}+\frac{\mathbf{y}}{\left(\mathrm{x}^{2}+\mathbf{y}^{2}\right)^{3 / 2}} \hat{\mathbf{j}}\right]$
( $k$ being constant of appropriate dimensions). When the particle is taken from the point $(\mathrm{a}, 0)$ to the point $(0$, a) along a circular path of radius a about the origin in the $x-y$ plane is

1 $2 \mathrm{k} \frac{\pi}{\mathrm{a}}$
2 $\mathrm{k} \frac{\pi}{\mathrm{a}}$
3 $\mathrm{k} \frac{\pi}{2 \mathrm{a}}$
4 0
Work, Energy and Power

148721 An elevator can carry a maximum load of 1000 $\mathrm{kg}$ is moving up with a constant speed of $2 \mathrm{~m} / \mathrm{s}$. The frictional force opposing the motion is $2000 \mathrm{~N}$. The minimum power delivered by the motor to the elevator is: (Assuming g=10 m/ $/ \mathrm{s}^{2}$ )

1 $18 \mathrm{~kW}$
2 $24 \mathrm{~kW}$
3 $20 \mathrm{~kW}$
4 $26 \mathrm{~kW}$
Work, Energy and Power

148722 A force $F=3 x^{2}+2 x+1$ acts on a body in the $x$ - direction. The work done by this force during a displacement from $x=-1$ to +1 is

1 2 units
2 4 units
3 6 units
4 8 units
Work, Energy and Power

148718 A force $\vec{F}=(5 \hat{i}+4 \hat{j}) N$ acts on a body and produces a displacement $\overrightarrow{\mathrm{S}}=(6 \hat{\mathbf{i}}-5 \hat{\mathbf{j}}+3 \hat{\mathbf{k}}) \mathrm{m}$. The work done by the force is

1 $10 \mathrm{~J}$
2 $20 \mathrm{~J}$
3 $30 \mathrm{~J}$
4 $40 \mathrm{~J}$
Work, Energy and Power

148719 The heart of a man pumps $5 \mathrm{~L}$ of blood through the arteries per minute at a pressure of $150 \mathrm{~mm}$ of mercury. If the density of mercury be $13.6 \times 10^{3} \mathrm{~kg} / \mathrm{m}^{3}$ and $\mathrm{g}=10 \mathrm{~m} / \mathrm{s}^{2}$, then the power of heart in watt is

1 1.70
2 2.35
3 3.0
4 1.50
Work, Energy and Power

148720 The work done on the particle of mass $M$ by a force, is given as
$\mathbf{k}\left[\frac{\mathbf{x}}{\left(\mathrm{x}^{2}+\mathbf{y}^{2}\right)^{3 / 2}} \hat{\mathbf{i}}+\frac{\mathbf{y}}{\left(\mathrm{x}^{2}+\mathbf{y}^{2}\right)^{3 / 2}} \hat{\mathbf{j}}\right]$
( $k$ being constant of appropriate dimensions). When the particle is taken from the point $(\mathrm{a}, 0)$ to the point $(0$, a) along a circular path of radius a about the origin in the $x-y$ plane is

1 $2 \mathrm{k} \frac{\pi}{\mathrm{a}}$
2 $\mathrm{k} \frac{\pi}{\mathrm{a}}$
3 $\mathrm{k} \frac{\pi}{2 \mathrm{a}}$
4 0
Work, Energy and Power

148721 An elevator can carry a maximum load of 1000 $\mathrm{kg}$ is moving up with a constant speed of $2 \mathrm{~m} / \mathrm{s}$. The frictional force opposing the motion is $2000 \mathrm{~N}$. The minimum power delivered by the motor to the elevator is: (Assuming g=10 m/ $/ \mathrm{s}^{2}$ )

1 $18 \mathrm{~kW}$
2 $24 \mathrm{~kW}$
3 $20 \mathrm{~kW}$
4 $26 \mathrm{~kW}$
Work, Energy and Power

148722 A force $F=3 x^{2}+2 x+1$ acts on a body in the $x$ - direction. The work done by this force during a displacement from $x=-1$ to +1 is

1 2 units
2 4 units
3 6 units
4 8 units
Work, Energy and Power

148718 A force $\vec{F}=(5 \hat{i}+4 \hat{j}) N$ acts on a body and produces a displacement $\overrightarrow{\mathrm{S}}=(6 \hat{\mathbf{i}}-5 \hat{\mathbf{j}}+3 \hat{\mathbf{k}}) \mathrm{m}$. The work done by the force is

1 $10 \mathrm{~J}$
2 $20 \mathrm{~J}$
3 $30 \mathrm{~J}$
4 $40 \mathrm{~J}$
Work, Energy and Power

148719 The heart of a man pumps $5 \mathrm{~L}$ of blood through the arteries per minute at a pressure of $150 \mathrm{~mm}$ of mercury. If the density of mercury be $13.6 \times 10^{3} \mathrm{~kg} / \mathrm{m}^{3}$ and $\mathrm{g}=10 \mathrm{~m} / \mathrm{s}^{2}$, then the power of heart in watt is

1 1.70
2 2.35
3 3.0
4 1.50
Work, Energy and Power

148720 The work done on the particle of mass $M$ by a force, is given as
$\mathbf{k}\left[\frac{\mathbf{x}}{\left(\mathrm{x}^{2}+\mathbf{y}^{2}\right)^{3 / 2}} \hat{\mathbf{i}}+\frac{\mathbf{y}}{\left(\mathrm{x}^{2}+\mathbf{y}^{2}\right)^{3 / 2}} \hat{\mathbf{j}}\right]$
( $k$ being constant of appropriate dimensions). When the particle is taken from the point $(\mathrm{a}, 0)$ to the point $(0$, a) along a circular path of radius a about the origin in the $x-y$ plane is

1 $2 \mathrm{k} \frac{\pi}{\mathrm{a}}$
2 $\mathrm{k} \frac{\pi}{\mathrm{a}}$
3 $\mathrm{k} \frac{\pi}{2 \mathrm{a}}$
4 0
Work, Energy and Power

148721 An elevator can carry a maximum load of 1000 $\mathrm{kg}$ is moving up with a constant speed of $2 \mathrm{~m} / \mathrm{s}$. The frictional force opposing the motion is $2000 \mathrm{~N}$. The minimum power delivered by the motor to the elevator is: (Assuming g=10 m/ $/ \mathrm{s}^{2}$ )

1 $18 \mathrm{~kW}$
2 $24 \mathrm{~kW}$
3 $20 \mathrm{~kW}$
4 $26 \mathrm{~kW}$
Work, Energy and Power

148722 A force $F=3 x^{2}+2 x+1$ acts on a body in the $x$ - direction. The work done by this force during a displacement from $x=-1$ to +1 is

1 2 units
2 4 units
3 6 units
4 8 units