Question
What force should be applied on the wedge so that block over it does not move? (All surfaces are smooth)
✓
Answer
(b)
$a =\left(\frac{ F }{ m + M }\right) \ldots \ldots(1)$
$m a \cos \theta=m g \sin \theta$
$a=g \tan \theta$
Put in $(1)$
$F=(M+m) g \tan \theta$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
Mean life of a radioactive sample is $100$ seconds. Then its half life (in minutes) is
→Projectiles $A$ and $B$ are thrown at angles of $45^{\circ}$ and $60^{\circ}$ with vertical respectively from top of a $400 \mathrm{~m}$ high tower. If their ranges and times of flight are same, the ratio of their speeds of projection $v_A: v_B$ is :
→One ice skater of mass $m$ moves with speed $2v$ to the right, while another of the same mass $m$ moves with speed $v$ toward the left, as shown in figure $I$. Their paths are separated by $a$ distance $b$. At $t = 0$, when they are both at $x = 0$, they grasp a pole of length $b$ and negligible mass. For $t > 0$, consider the system as a rigid body of two masses $m$ separated by distance $b$, as shown in figure $II$. Which of the following is the correct formula for the motion after $t = 0$ of the skater initially at $y = b/2?$
→Volt/metre is the unit of
A wire of length $L,$ area of cross section $A$ is hanging from a fixed support. The length of the wire changes to $L_{1}$ when mass $M$ is suspended from its free end. The expression for Young's modulus is
→In the ladder network shown, current through the resistor $3\, \Omega$ is $0.25\,A$. The input voltage $'V'$ is equal to:- ........... $V$
→The mass per unit length of a uniform wire is $0.135\, g / cm$. A transverse wave of the form $y =-0.21 \sin ( x +30 t )$ is produced in it, where $x$ is in meter and $t$ is in second. Then, the expected value of tension in the wire is $x \times 10^{-2} N$. Value of $x$ is . (Round-off to the nearest integer)
→$Assertion$ : Use of ball bearings between two moving parts of a machine is a common practice.
$Reason$ : Ball bearings reduce vibrations and provide good stability.
→$Reason$ : Ball bearings reduce vibrations and provide good stability.
A diatomic gas undergoes a process represented by $PV ^{1.3}=$ constant. Choose the incorrect statement
→Magnetic flux (in weber) in a closed circuit of resistance $20\,\Omega$ varies with time $t(s)$ as $\phi=8 t ^{2}-9 t +5$. The magnitude of the induced current at $t =0.25\,s$ will be $...mA$
→