1
NEET 2013 (Karnataka)
MCQ (Single Correct Answer)
+4
-1
Change Language
One coolie takes 1 minute to raise a suitcase through a height of 2 m but the second coolie takes 30 s to raise the same suitcase to the same height. The powers of two coolies are in the ratio
A
1 : 3
B
2 : 1
C
3 : 1
D
1 : 2
2
NEET 2013 (Karnataka)
MCQ (Single Correct Answer)
+4
-1
Change Language
A person holding a rifle (mass of person and rifle together is 100 kg) stands on a smooth surface and fires 10 shots horizontally, in 5 s. Each bullet has a mass of 10 g with a muzzle velocity of 800 m s$$-$$1. The final velocity acquired by the person and the average force exerted on the person are :
A
$$-$$0.08 ms$$-$$1, 16 N
B
$$-$$0.8 ms$$-$$1, 8 N
C
$$-$$1.6 ms$$-$$1, 16 N
D
$$-$$1.6 ms$$-$$1, 8 N
3
NEET 2013 (Karnataka)
MCQ (Single Correct Answer)
+4
-1
Change Language
The ratio of radii of gyration of a circular ring and a circular disc, of the same mass and radius, about an axis passing through their centres and perpendicular to their planes are
A
$$1:\sqrt 2 $$
B
3 : 2
C
2 : 1
D
$$\sqrt 2 :1$$
4
NEET 2013 (Karnataka)
MCQ (Single Correct Answer)
+4
-1
Change Language
Two discs are rotating about their axes, normal to the discs and passing through the centres of the discs. Disc D1 has 2 kg mass and 0.2 m radius and initial angular velocity of 50 rad s$$-$$1. Disc D2 has 4 kg mass, 0.1 m radius and initial angular velocity of 200 rad s$$-$$1. The two discs are brought in contact face to face, with their axes of rotation coincident. The final angular velocity (in rad s$$-$$1) of the system is
A
60
B
100
C
120
D
40