5 J
10 J
15 J
20 J
Correct answer is C
Height h = 1/2 (U\(^2\)/g) = 10\(^2\)/20 = 5m
Energy before hitting ground is = P.E at the height of 5m.
P.E = mgh = 0.1 x 10 x 10= 10 J
K.E = 1/2 MV\(^2\) = 5J
T.E = K.E + P.E = 5 + 10 = 15J
50 J
100 J
150 J
200 J
Correct answer is A
From principle of conservation of linear momentum,
(0.05 x 200) + (0.95 x 0) = (0.05 + 0.95) x V (since collision is inelastic).
10 + 0 = V
Thus V = 10m/s.
Recall Kinetic Energy = \(\frac{1}{2} mv^2\)
\(\therefore\) K.E = 1/2 (0.05 + 0.95) x 10\(^2\)
K.E = 1/2 (1 x 100) = 50 J.
2 N
20 N
200 N
400 N
Correct answer is B
Centripetal Force (F\(_c\)) = \(\frac{mv ^2}{r}\)
= \(mω^2r\)
(Since V = ωr)
F = 100 x 0.2
F =20 N
1 : 4
2 : 1
2 : 3
2 : 5
Correct answer is C
Let the forces be F1, and F2.
F1 = m1 a1 = 3 x 2 = 6N
F2 = m2 a2 = 1 x 9 = 9N
F1 : F2 = 6:9 = 2:3
Thus ratio of forces is 2: 3
The inner diameter of a test tube can be measured accurately using a?
micrometer screw guage
pair of dividers
metre rule
pair of vernier calipers
Correct answer is D
A Vernier caliper is an instrument used to measure both the outer and inner diameters of a tube.