An alpha nucleus of energy bombards a heavy nuclear target of charge Ze. Then the distance of closest approach for the alpha nucleus will be proportional to
v2
1/ m
1/ν4
1/ Ze
Diwali rocket is ejecting 50 g of gases/s at a velocity of 400 m/s. The accelerating force on the rocket will be
22 dyne
20 N
20 dyne
100 N
B.
20 N
The accelerating force on the rocket
= upward thrust =
Given:-
,
ν = 400 m/s
Accelerating force = 50 × 10 × 400
= 20 N
The maximum number of possible interference maxima for slit-separation equal to twice the wavelength in Young's double slit experiment is
infinite
five
three
zero
A particle executes simple harmonic oscillation with an amplitude . The period of oscillation is T. The minimum time taken by the particle to travel half of the amplitude from the equilibrium position is
An observer moves towards a stationary source of sound, with a velocity one-fifth of the velocity of sound. What is the percentage increase in the apparent frequency ?
Zero
0.5 %
5 %
20 %
Which of the following parameters does not characterise the thermodynamic state of matter?
Temperature
Pressure
Work
Volume
A charged oil drop is suspended in uniform field of 3 x 104 V/m so that it neither falls nor rises. The charge on the drop will be (Take the mass of the charge = 9.9 x 10-15 kg and g = 10 m/s2 )
3.3 × 10-18 C
3.2 × 10-18 C
1.6 × 10-18 C
4.8 × 10-18 C
The work of 146 kJ is performed in order to compress one kilo mole of a gas adiabatically and in this process the temperature of the gas increases by 7°C. The gas is (R= 8.3J mol-1 K-1 )
diatomic
triatomic
a mixture of monoatomic and diatomic
monoatomic
A frame made of metallic wire enclosing a surface area A is covered with a soap film. If the area of the frame of metallic wire is reduced by 50%, the energy of the soap film will be changed by
100%
75%
50%
25%
Mercury boils at 367oC. However, mercury thermometers are made such that they can measure temperature upto 500oC. This is done by
maintaining vacuum above mercury column in the stem of the thermometer
filling nitrogen gas at high pressure above the mercury column
filling oxygen gas at high pressure above the mercury column
filling nitrogen gas at low pressure above the mercury column