Physics
The impurity atoms with which silicon should be doped to make p-type semiconductors are

Germanium
Boron
Phosphorus
Antimony

ANSWER DOWNLOAD EXAMIANS APP

Physics
In total internal reflection, the light travel from

Rarer to denser medium and it occurs with loss of intensity
Denser to rarer medium and it occurs with no loss of intensity
Rarer to denser medium and it occurs with no loss of intensity
Denser to rarer medium and it occurs with loss of intensity

ANSWER DOWNLOAD EXAMIANS APP

Physics
A metal ball and a rubber ball, both having the same mass, strike a wall normally with the same velocity. The rubber ball rebounds and the metal ball does not rebound. It can be concluded that

The rubber ball suffers greater change in momentum
Both suffer the same change in momentum
The metal ball suffers greater change in momentum
The initial momentum of the rubber ball is greater than that of the metal ball

ANSWER DOWNLOAD EXAMIANS APP