Friction
PHXI05:LAWS OF MOTION

363365 A given object takes \(n\) times the time to slide down \(45^{\circ}\) rough inclined plane as it takes the time to slide down an identical perfectly smooth \(45^{\circ}\) inclined plane. The coefficient of kinetic friction between the object and the surface of inclined plane is

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

363366 Block \(A\) of mass \(m\) and block \(B\) of mass 2 \(m\) are placed on a fixed triangular wedge by means of massless, inextensible string and a frictionless pulley as shown. The wedge is inclined at \(45^\circ \) to horizontal on both sides. The coefficient of friction between block \(A\) and wedge is 2/3 and between block \(B\) and wedge is 1/3. If system of \(A\) and \(B\) is released from rest then acceleration of \(A\) is
supporting img

1 \({\rm{Zero}}\)
2 \(1\,m{s^{ - 2}}\)
3 \(2\,m{s^{ - 2}}\)
4 \(3\,m{s^{ - 2}}\)
PHXI05:LAWS OF MOTION

363367 A block can slide down the incline plane with constant velocity. If it is projected with a velocity ‘\(u\)’ up the incline at \(t = 0\). The displacement of block after a time \(t = \frac{u}{{g\sin \theta }}\) from \(O\) will be
supporting img

1 \(\frac{{{u^2}}}{{2\,g\sin \theta }}\)
2 \({\rm{zero}}\)
3 \(\frac{{{u^2}}}{{4\,g\cos \theta }}\)
4 \(\frac{{{u^2}}}{{4\,g\sin \theta }}\)
PHXI05:LAWS OF MOTION

363368 Two blocks of masses \({m_{1}=m_{2}=m}\) are connected by a string of negligible mass, which passes over a frictionless pulley connected with a plane, as shown in the figure. When the inclination \({\theta=45^{\circ}}\), the mass \({m_{1}}\) begins to move up the inclined plane. What is the coefficient of friction between block \({m_{1}}\) and the inclined planes?
supporting img

1 \({\dfrac{\sqrt{2}-1}{3}}\)
2 \({\dfrac{1}{\sqrt{2}}}\)
3 \({\sqrt{2}-1}\)
4 \({\dfrac{1}{\sqrt{3}}}\)
PHXI05:LAWS OF MOTION

363365 A given object takes \(n\) times the time to slide down \(45^{\circ}\) rough inclined plane as it takes the time to slide down an identical perfectly smooth \(45^{\circ}\) inclined plane. The coefficient of kinetic friction between the object and the surface of inclined plane is

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

363366 Block \(A\) of mass \(m\) and block \(B\) of mass 2 \(m\) are placed on a fixed triangular wedge by means of massless, inextensible string and a frictionless pulley as shown. The wedge is inclined at \(45^\circ \) to horizontal on both sides. The coefficient of friction between block \(A\) and wedge is 2/3 and between block \(B\) and wedge is 1/3. If system of \(A\) and \(B\) is released from rest then acceleration of \(A\) is
supporting img

1 \({\rm{Zero}}\)
2 \(1\,m{s^{ - 2}}\)
3 \(2\,m{s^{ - 2}}\)
4 \(3\,m{s^{ - 2}}\)
PHXI05:LAWS OF MOTION

363367 A block can slide down the incline plane with constant velocity. If it is projected with a velocity ‘\(u\)’ up the incline at \(t = 0\). The displacement of block after a time \(t = \frac{u}{{g\sin \theta }}\) from \(O\) will be
supporting img

1 \(\frac{{{u^2}}}{{2\,g\sin \theta }}\)
2 \({\rm{zero}}\)
3 \(\frac{{{u^2}}}{{4\,g\cos \theta }}\)
4 \(\frac{{{u^2}}}{{4\,g\sin \theta }}\)
PHXI05:LAWS OF MOTION

363368 Two blocks of masses \({m_{1}=m_{2}=m}\) are connected by a string of negligible mass, which passes over a frictionless pulley connected with a plane, as shown in the figure. When the inclination \({\theta=45^{\circ}}\), the mass \({m_{1}}\) begins to move up the inclined plane. What is the coefficient of friction between block \({m_{1}}\) and the inclined planes?
supporting img

1 \({\dfrac{\sqrt{2}-1}{3}}\)
2 \({\dfrac{1}{\sqrt{2}}}\)
3 \({\sqrt{2}-1}\)
4 \({\dfrac{1}{\sqrt{3}}}\)
PHXI05:LAWS OF MOTION

363365 A given object takes \(n\) times the time to slide down \(45^{\circ}\) rough inclined plane as it takes the time to slide down an identical perfectly smooth \(45^{\circ}\) inclined plane. The coefficient of kinetic friction between the object and the surface of inclined plane is

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

363366 Block \(A\) of mass \(m\) and block \(B\) of mass 2 \(m\) are placed on a fixed triangular wedge by means of massless, inextensible string and a frictionless pulley as shown. The wedge is inclined at \(45^\circ \) to horizontal on both sides. The coefficient of friction between block \(A\) and wedge is 2/3 and between block \(B\) and wedge is 1/3. If system of \(A\) and \(B\) is released from rest then acceleration of \(A\) is
supporting img

1 \({\rm{Zero}}\)
2 \(1\,m{s^{ - 2}}\)
3 \(2\,m{s^{ - 2}}\)
4 \(3\,m{s^{ - 2}}\)
PHXI05:LAWS OF MOTION

363367 A block can slide down the incline plane with constant velocity. If it is projected with a velocity ‘\(u\)’ up the incline at \(t = 0\). The displacement of block after a time \(t = \frac{u}{{g\sin \theta }}\) from \(O\) will be
supporting img

1 \(\frac{{{u^2}}}{{2\,g\sin \theta }}\)
2 \({\rm{zero}}\)
3 \(\frac{{{u^2}}}{{4\,g\cos \theta }}\)
4 \(\frac{{{u^2}}}{{4\,g\sin \theta }}\)
PHXI05:LAWS OF MOTION

363368 Two blocks of masses \({m_{1}=m_{2}=m}\) are connected by a string of negligible mass, which passes over a frictionless pulley connected with a plane, as shown in the figure. When the inclination \({\theta=45^{\circ}}\), the mass \({m_{1}}\) begins to move up the inclined plane. What is the coefficient of friction between block \({m_{1}}\) and the inclined planes?
supporting img

1 \({\dfrac{\sqrt{2}-1}{3}}\)
2 \({\dfrac{1}{\sqrt{2}}}\)
3 \({\sqrt{2}-1}\)
4 \({\dfrac{1}{\sqrt{3}}}\)
PHXI05:LAWS OF MOTION

363365 A given object takes \(n\) times the time to slide down \(45^{\circ}\) rough inclined plane as it takes the time to slide down an identical perfectly smooth \(45^{\circ}\) inclined plane. The coefficient of kinetic friction between the object and the surface of inclined plane is

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

363366 Block \(A\) of mass \(m\) and block \(B\) of mass 2 \(m\) are placed on a fixed triangular wedge by means of massless, inextensible string and a frictionless pulley as shown. The wedge is inclined at \(45^\circ \) to horizontal on both sides. The coefficient of friction between block \(A\) and wedge is 2/3 and between block \(B\) and wedge is 1/3. If system of \(A\) and \(B\) is released from rest then acceleration of \(A\) is
supporting img

1 \({\rm{Zero}}\)
2 \(1\,m{s^{ - 2}}\)
3 \(2\,m{s^{ - 2}}\)
4 \(3\,m{s^{ - 2}}\)
PHXI05:LAWS OF MOTION

363367 A block can slide down the incline plane with constant velocity. If it is projected with a velocity ‘\(u\)’ up the incline at \(t = 0\). The displacement of block after a time \(t = \frac{u}{{g\sin \theta }}\) from \(O\) will be
supporting img

1 \(\frac{{{u^2}}}{{2\,g\sin \theta }}\)
2 \({\rm{zero}}\)
3 \(\frac{{{u^2}}}{{4\,g\cos \theta }}\)
4 \(\frac{{{u^2}}}{{4\,g\sin \theta }}\)
PHXI05:LAWS OF MOTION

363368 Two blocks of masses \({m_{1}=m_{2}=m}\) are connected by a string of negligible mass, which passes over a frictionless pulley connected with a plane, as shown in the figure. When the inclination \({\theta=45^{\circ}}\), the mass \({m_{1}}\) begins to move up the inclined plane. What is the coefficient of friction between block \({m_{1}}\) and the inclined planes?
supporting img

1 \({\dfrac{\sqrt{2}-1}{3}}\)
2 \({\dfrac{1}{\sqrt{2}}}\)
3 \({\sqrt{2}-1}\)
4 \({\dfrac{1}{\sqrt{3}}}\)