The product$(s)$ formed when $H_2O_2$ reacts with disodium hydrogen phosphate is

$A$ person walks along a straight road from his house to a market $2.5 \ km$ away with a speed of $5 \ km/h$ and instantly turns back and reaches his house with a speed of $7.5 \ km/h$. The average speed of the person during the time interval $0$ to $50 \ min$ is (in $m/s$):

Which of the following is not a hereditary disease?

$A$ piece of semiconductor is connected in series in an electric circuit. On increasing the temperature,the current in the circuit will

An electrically charged particle enters a uniform magnetic field in a direction perpendicular to the field with a velocity $v$. Then,it travels

The refractive index of a material of a plano-concave lens is $5/3$,and the radius of curvature is $0.3 ~m$. The focal length of the lens in air is (in $~m$)