Total internal reflection is possible when light travels from
air to water
air to glass
water to glass
glass to water
The potential difference across a conductor of resistivity e is constant. The heat generated in the conductor is directly proportional to
e
e2
A body of mass 2 kg is moving on a smooth horizontal surface with an initial velocity of 10 ms-1 along the east. A uniform force of 10 N towards the north is applied to the body. The final velocity of the body after 2 s will be
ms-1 at 45° North of East
ms-1 at 45° South of East
20 ms-1 towards East
20 ms-1 towards West
Which of the following gives precipitate, with ammoniacal silver nitrate solution?
C2H6 (Ethane)
C2H4 (Ethylene)
C2H2 (Acetylene)
C3H6 (Propene)
The compound responsible for the temporary hardness of water is
Mg(HCO3)2
CaCl2
MgSO4
CaCO3
A.
Mg(HCO3)2
Temporary hardness of water is because of the presence of bicarbonate of calcium and magnesium. It can be easily removed by just boiling and filtering the water.