Friction
PHXI05:LAWS OF MOTION

363360 A smooth block is released from rest on a \(45^{\circ}\) smooth incline, it sildes a distance \(d\). If it slides same distance on a \(45^{\circ}\) rough incline, the time it takes is ' \(n\) ' times that on identical smooth incline, then the coefficient of friction on rough incline is

1 \(\mu_{k}=1-\dfrac{1}{n^{2}}\)
2 \(\mu_{k}=\sqrt{1-\dfrac{1}{n^{2}}}\)
3 \(\mu_{s}=1-\dfrac{1}{n^{2}}\)
4 \(\mu_{s}=\sqrt{1-\dfrac{1}{n^{2}}}\)
PHXI05:LAWS OF MOTION

363361 A body is projected up a \({\rm{45}}^\circ \) rough incline. If the coefficient of friction is 0.5, then the retardation of the block is

1 \(\frac{g}{{2\sqrt 2 }}\)
2 \(\frac{g}{{\sqrt 2 }}\)
3 \(\frac{{3g}}{{2\sqrt 2 }}\)
4 \(\frac{g}{2}\)
PHXI05:LAWS OF MOTION

363362 Two stationary blocks \(A\) and \(B\) of equal masses are released from an inclined plane of inclination \(60^{\circ}\) at \(t = 0.\) The coefficient of kinetic friction between the block \(A\) and the inclined plane is \(0.4\) while it is \(0.6\) for block \(B\). Initially the block \(A\) is \(2.4\;m\) behind the block \(B\). Both the blocks will come in a line after \(A\) has travelled a distance of how much down the plane.
(Take \(g = 10\;m{\rm{/}}{s^2}\) and \(\sqrt 3 = 1.73\)
supporting img

1 \(17.45\,m\)
2 \(15.95\,m\)
3 \(19.23\,m\)
4 \(20.95\,m\)
PHXI05:LAWS OF MOTION

363363 A block kept on a rough surface starts sliding when the inclination of the surface is ‘\(\theta \)’ with respect to the horizontal. The coefficient of static friction between the block and the surface is

1 \(\sin \theta \)
2 \(\tan \theta \)
3 \(\cos \theta \)
4 \(\sec \theta \)
PHXI05:LAWS OF MOTION

363364 Two blocks are connected over a massless pulley as shown in fig. The mass of block \(A\) is \(10\;kg\) and the coefficient of kinetic friction is 0.2. Block \(A\) slides down the incline constant speed. The mass of block \(B\) in \(kg\) is:
supporting img

1 3.5
2 3.3
3 3.0
4 2.5
PHXI05:LAWS OF MOTION

363360 A smooth block is released from rest on a \(45^{\circ}\) smooth incline, it sildes a distance \(d\). If it slides same distance on a \(45^{\circ}\) rough incline, the time it takes is ' \(n\) ' times that on identical smooth incline, then the coefficient of friction on rough incline is

1 \(\mu_{k}=1-\dfrac{1}{n^{2}}\)
2 \(\mu_{k}=\sqrt{1-\dfrac{1}{n^{2}}}\)
3 \(\mu_{s}=1-\dfrac{1}{n^{2}}\)
4 \(\mu_{s}=\sqrt{1-\dfrac{1}{n^{2}}}\)
PHXI05:LAWS OF MOTION

363361 A body is projected up a \({\rm{45}}^\circ \) rough incline. If the coefficient of friction is 0.5, then the retardation of the block is

1 \(\frac{g}{{2\sqrt 2 }}\)
2 \(\frac{g}{{\sqrt 2 }}\)
3 \(\frac{{3g}}{{2\sqrt 2 }}\)
4 \(\frac{g}{2}\)
PHXI05:LAWS OF MOTION

363362 Two stationary blocks \(A\) and \(B\) of equal masses are released from an inclined plane of inclination \(60^{\circ}\) at \(t = 0.\) The coefficient of kinetic friction between the block \(A\) and the inclined plane is \(0.4\) while it is \(0.6\) for block \(B\). Initially the block \(A\) is \(2.4\;m\) behind the block \(B\). Both the blocks will come in a line after \(A\) has travelled a distance of how much down the plane.
(Take \(g = 10\;m{\rm{/}}{s^2}\) and \(\sqrt 3 = 1.73\)
supporting img

1 \(17.45\,m\)
2 \(15.95\,m\)
3 \(19.23\,m\)
4 \(20.95\,m\)
PHXI05:LAWS OF MOTION

363363 A block kept on a rough surface starts sliding when the inclination of the surface is ‘\(\theta \)’ with respect to the horizontal. The coefficient of static friction between the block and the surface is

1 \(\sin \theta \)
2 \(\tan \theta \)
3 \(\cos \theta \)
4 \(\sec \theta \)
PHXI05:LAWS OF MOTION

363364 Two blocks are connected over a massless pulley as shown in fig. The mass of block \(A\) is \(10\;kg\) and the coefficient of kinetic friction is 0.2. Block \(A\) slides down the incline constant speed. The mass of block \(B\) in \(kg\) is:
supporting img

1 3.5
2 3.3
3 3.0
4 2.5
PHXI05:LAWS OF MOTION

363360 A smooth block is released from rest on a \(45^{\circ}\) smooth incline, it sildes a distance \(d\). If it slides same distance on a \(45^{\circ}\) rough incline, the time it takes is ' \(n\) ' times that on identical smooth incline, then the coefficient of friction on rough incline is

1 \(\mu_{k}=1-\dfrac{1}{n^{2}}\)
2 \(\mu_{k}=\sqrt{1-\dfrac{1}{n^{2}}}\)
3 \(\mu_{s}=1-\dfrac{1}{n^{2}}\)
4 \(\mu_{s}=\sqrt{1-\dfrac{1}{n^{2}}}\)
PHXI05:LAWS OF MOTION

363361 A body is projected up a \({\rm{45}}^\circ \) rough incline. If the coefficient of friction is 0.5, then the retardation of the block is

1 \(\frac{g}{{2\sqrt 2 }}\)
2 \(\frac{g}{{\sqrt 2 }}\)
3 \(\frac{{3g}}{{2\sqrt 2 }}\)
4 \(\frac{g}{2}\)
PHXI05:LAWS OF MOTION

363362 Two stationary blocks \(A\) and \(B\) of equal masses are released from an inclined plane of inclination \(60^{\circ}\) at \(t = 0.\) The coefficient of kinetic friction between the block \(A\) and the inclined plane is \(0.4\) while it is \(0.6\) for block \(B\). Initially the block \(A\) is \(2.4\;m\) behind the block \(B\). Both the blocks will come in a line after \(A\) has travelled a distance of how much down the plane.
(Take \(g = 10\;m{\rm{/}}{s^2}\) and \(\sqrt 3 = 1.73\)
supporting img

1 \(17.45\,m\)
2 \(15.95\,m\)
3 \(19.23\,m\)
4 \(20.95\,m\)
PHXI05:LAWS OF MOTION

363363 A block kept on a rough surface starts sliding when the inclination of the surface is ‘\(\theta \)’ with respect to the horizontal. The coefficient of static friction between the block and the surface is

1 \(\sin \theta \)
2 \(\tan \theta \)
3 \(\cos \theta \)
4 \(\sec \theta \)
PHXI05:LAWS OF MOTION

363364 Two blocks are connected over a massless pulley as shown in fig. The mass of block \(A\) is \(10\;kg\) and the coefficient of kinetic friction is 0.2. Block \(A\) slides down the incline constant speed. The mass of block \(B\) in \(kg\) is:
supporting img

1 3.5
2 3.3
3 3.0
4 2.5
PHXI05:LAWS OF MOTION

363360 A smooth block is released from rest on a \(45^{\circ}\) smooth incline, it sildes a distance \(d\). If it slides same distance on a \(45^{\circ}\) rough incline, the time it takes is ' \(n\) ' times that on identical smooth incline, then the coefficient of friction on rough incline is

1 \(\mu_{k}=1-\dfrac{1}{n^{2}}\)
2 \(\mu_{k}=\sqrt{1-\dfrac{1}{n^{2}}}\)
3 \(\mu_{s}=1-\dfrac{1}{n^{2}}\)
4 \(\mu_{s}=\sqrt{1-\dfrac{1}{n^{2}}}\)
PHXI05:LAWS OF MOTION

363361 A body is projected up a \({\rm{45}}^\circ \) rough incline. If the coefficient of friction is 0.5, then the retardation of the block is

1 \(\frac{g}{{2\sqrt 2 }}\)
2 \(\frac{g}{{\sqrt 2 }}\)
3 \(\frac{{3g}}{{2\sqrt 2 }}\)
4 \(\frac{g}{2}\)
PHXI05:LAWS OF MOTION

363362 Two stationary blocks \(A\) and \(B\) of equal masses are released from an inclined plane of inclination \(60^{\circ}\) at \(t = 0.\) The coefficient of kinetic friction between the block \(A\) and the inclined plane is \(0.4\) while it is \(0.6\) for block \(B\). Initially the block \(A\) is \(2.4\;m\) behind the block \(B\). Both the blocks will come in a line after \(A\) has travelled a distance of how much down the plane.
(Take \(g = 10\;m{\rm{/}}{s^2}\) and \(\sqrt 3 = 1.73\)
supporting img

1 \(17.45\,m\)
2 \(15.95\,m\)
3 \(19.23\,m\)
4 \(20.95\,m\)
PHXI05:LAWS OF MOTION

363363 A block kept on a rough surface starts sliding when the inclination of the surface is ‘\(\theta \)’ with respect to the horizontal. The coefficient of static friction between the block and the surface is

1 \(\sin \theta \)
2 \(\tan \theta \)
3 \(\cos \theta \)
4 \(\sec \theta \)
PHXI05:LAWS OF MOTION

363364 Two blocks are connected over a massless pulley as shown in fig. The mass of block \(A\) is \(10\;kg\) and the coefficient of kinetic friction is 0.2. Block \(A\) slides down the incline constant speed. The mass of block \(B\) in \(kg\) is:
supporting img

1 3.5
2 3.3
3 3.0
4 2.5
PHXI05:LAWS OF MOTION

363360 A smooth block is released from rest on a \(45^{\circ}\) smooth incline, it sildes a distance \(d\). If it slides same distance on a \(45^{\circ}\) rough incline, the time it takes is ' \(n\) ' times that on identical smooth incline, then the coefficient of friction on rough incline is

1 \(\mu_{k}=1-\dfrac{1}{n^{2}}\)
2 \(\mu_{k}=\sqrt{1-\dfrac{1}{n^{2}}}\)
3 \(\mu_{s}=1-\dfrac{1}{n^{2}}\)
4 \(\mu_{s}=\sqrt{1-\dfrac{1}{n^{2}}}\)
PHXI05:LAWS OF MOTION

363361 A body is projected up a \({\rm{45}}^\circ \) rough incline. If the coefficient of friction is 0.5, then the retardation of the block is

1 \(\frac{g}{{2\sqrt 2 }}\)
2 \(\frac{g}{{\sqrt 2 }}\)
3 \(\frac{{3g}}{{2\sqrt 2 }}\)
4 \(\frac{g}{2}\)
PHXI05:LAWS OF MOTION

363362 Two stationary blocks \(A\) and \(B\) of equal masses are released from an inclined plane of inclination \(60^{\circ}\) at \(t = 0.\) The coefficient of kinetic friction between the block \(A\) and the inclined plane is \(0.4\) while it is \(0.6\) for block \(B\). Initially the block \(A\) is \(2.4\;m\) behind the block \(B\). Both the blocks will come in a line after \(A\) has travelled a distance of how much down the plane.
(Take \(g = 10\;m{\rm{/}}{s^2}\) and \(\sqrt 3 = 1.73\)
supporting img

1 \(17.45\,m\)
2 \(15.95\,m\)
3 \(19.23\,m\)
4 \(20.95\,m\)
PHXI05:LAWS OF MOTION

363363 A block kept on a rough surface starts sliding when the inclination of the surface is ‘\(\theta \)’ with respect to the horizontal. The coefficient of static friction between the block and the surface is

1 \(\sin \theta \)
2 \(\tan \theta \)
3 \(\cos \theta \)
4 \(\sec \theta \)
PHXI05:LAWS OF MOTION

363364 Two blocks are connected over a massless pulley as shown in fig. The mass of block \(A\) is \(10\;kg\) and the coefficient of kinetic friction is 0.2. Block \(A\) slides down the incline constant speed. The mass of block \(B\) in \(kg\) is:
supporting img

1 3.5
2 3.3
3 3.0
4 2.5