54618.When an object falls freely towards the ground, then its total energy:
Increases
Decreases
Remains constant
First increases then decreases
54620.What happens to the body on which work is done:
It loses energy
It gains energy
No change in the energy
First it loses then it gain
54621.To get output 1 for the following circuit, the correct choice for the input is:
A = 0, B = 1, C = 0
A = 1, B = 0, C = 0
A = 1, B = 1, C = 0
A = 1, B = 0, C = 1
54622.Two non-mixing liquids of densities $\\rho$ and n $\\rho$ (n > 1) are put in a container. The height of each liquids is h. A solid cylinder of length L and density d is put in this container. The cylinder floats with its axis vertical and length pL (p < 1) in the denser liquids. The density d is equal to
{1+(n+1)p}p
{2+(n+1)p}p
{2+{n-1}p}p
{1+(n-1)p}p
54623.A astronomical telescope has objective and eyepiece of focal lengths 40 cm and 4 cm respectively. To view an object 200 cm away from the objective, the lenses must be separated by a distance
37.3 cm
46.0 cm
50.0 cm
54.0 cm
54624.A radio set of 60 watts runs for 50 hours. How many units of electrical energy are consumed in
kWh?
kWh?
2 kWh
3 kWh
4 kWh
2.5 kWh
54628.Equimolar solutions of the following compounds are prepared separately in water. Which will have the lowest pH value?
BeCl2
SrCl2
CaCl2
MgCl2
54630.At a certain temperature 2HI ⥨ H2 + I2 only 50% HI is dissociated at equilibrium. The equilibrium constant is
0.25
1.0
3.0
0.6
54631.0.1M solution of which of the substances will behave basic?
sodium borate
ammonium chloride
calcium nitrate
sodium sulphate
54632.According to Le Chatelier’s principle adding heat to a solid and liquid in equilibrium will cause the
amount of solid to decrease
amount of liquid to decrease
temperature to rise
temperature to fall
54633.Addition of which chemical will decrease the hydrogen ion concentration of an acetic acid solution
NHCl
Al2(SO4)3
AgNO3
NaCN
54636.All compounds are in equilibrium in a reversible reaction. If increasing is doubled in concentration the equilibrium constant would be
reduced to half its original value
reduced to one fourth of its original value
doubled
constant
54637.In some solutions the concentration of H3O+ remains constant even when small amounts of strong acid or strong base are added to them. These solutions are known as
ideal solution
colloidal solution
true solution
buffer solution