Q. 14
Ablock ofmass m is projected on a smooth horizontal circular track with velocity v. What is average normal force exerted by the circular walls on the block during its motionfromAtoB. <
<
Q. 15 Two particles starts moving on the same circle of radius 2 m,fromthe same point P at t=0, with constant tangential accelerations=2 m/s2 and 6 m/s2, clockwise and anticlockwise, respectively. The point where they meet for thefirsttime is Q. The smaller angle subtended by PQ at center of circle is (A) 120° (B) 60° (C) 135° (D) 90° Q.16
A stunt manjumps his car over a crater as shown (neglect air resistance) (A) during the whole flight the driver experiences weightlessness (B) during the whole flight the driver never experiences weightlessness (C) during the whole flight the driver experiences weightlessness only at the highest point (D) the apparent weight increases during upward journey
Q. 17 A single wire ACB passes through a smooth ring at C which revolves at a constant speed in the horizontal circle ofradius r as shown in thefig.The speed of revolution is (A).Vig
(C) 2A/2rg
\
A g
bo1
(D) 2 ^
Q. 18 AB is the vertical diameter of a circle in a vertical plane. Another diameter CD makes an angle of 60° with AB; then the ratio ofthe time taken by a particle to slide along AB to the time taken by it to slide along CD, is (A) 1:1
(B) 4%: 1
(C)3 1 / 4 :2 1 / 2
(D) 1: 4 2
Q. 19 A body is thrown with a velocity of 10 m/s at an angle of 45° to the horizontal. The radius of curvature of its trajectory in t = 1/V2 sec after the body began to move is: (A)0m
-(B) 2.5 m
(C)5m
(D)None
Q.20
On a particle moving on a circular path with a constant speed v, light is thrown from a projectors placed at the centre of the circular path. The shadow ofthe particle is formed on the wall, the velocity of shadow up the wall is (A)vsec2(j) (B)VCOS2(|) (C) (A) vcos<j) (D)none
Q.21
The length of second's hand in a watchis 1 cm. The change in velocity of its tip in 15 sec is: (A) zero
Q. 22
(C) tt/30 cm/s
(D) 7tV2/30 cm/s
Apoint P moves along a circle ofradius r with constant speed v. Its angular velocity about anyfixedpoint on the circle will be (A) v/r
Q.23
(B) 71/3 0V2 cm/s
gj wall
(B)v/2r
..(C) y/r 2
(D) v / 2 r 2
A heavy particle hangingfroma string oflength I is projected horizontally with speed JgT. Thespeed of the particle at the point where the tension in the string equals weight ofthe particle is: (A)^iI
(B)V3g7
(C) J & 7 2
(D)v973