13-02-2013, 04:24 PM
TESTBOOKLET PHYSICALSCIENCES
TESTBOOKLET .pdf (Size: 1.15 MB / Downloads: 74)
1. A meteorite moves under a force .If r
denotes its position vector, then which of the following are
correct ?
1. Its linear momentum is conserved.
2. Its angular momentum is conserved.
3. Its torque vanishes
Select the correct answer using the code given below :
(a) 1 and 2 only (b) 1 and 3 only © 2 and 3 only (d) 1 , 2 and 3
Ans. (d)
Sol. It is the central force so that 1,2 and 3 are correct.
2. Consider the following statements : Nuclear force is :
1. charge independent
2. long range
3. central
Which of the above statements is/are correct?
(a) 1 only (b) 1 and 2 © 2 and 3 (d) 1 and 3
Ans. (a)
Sol. Change independent.
3. What will happen when a 40 W, 220 V lamp and 100 W, 220 V lamp are connected in series across 440 V
supply
(a) 40W lamp will fuse. (b) 100W lamp will fuse.
© Both the lamps will fuse. (d) Neither lamp will fuse.
Ans. (a)
Sol. R40W > R100W so that potential drop across 40W bulb will be greater than 220 V & it will fuse.
4. A particle executing SHM has kinetic energy ko cos2 t. The maximum values of potential energy and total
energy are respectively
(a) o
o andk
2
k
(b) k0 and 2 k0 © k0 and k0 (d) 0 and 2k0
Ans. ©
Sol. Kmax = P.E.max = T.E. which is constant.
So that P.E.max = T.E. = k0 .
5. Consider a point P, the contact point of a wheel of radius r on the ground which rolls on the ground without
slipping. What is the displacement of point P, when the wheel completes half rotation ?
(a) 2 r (b) r © r 2 4 (d) r 2 2