A) mercury thermometers | B) alcohol thermometers |

C) platinum resistance thermometers | D) thermoelectric thermometers |

Explanation:

The resistance of metallic conductors e.g, platinum, increases with rise of temperature . The increase in temperature results in a decrease of current which can be recorded in a galvanometer if the conductor is included in an electrical circuit. Thus the temperature can be known; platinum resistance thermometer is used generally for accurate scientific work. When two dissimilar metals are joined at the ends, and these ends are subjected to a difference of temperature, a current flows through the metals. Greater the difference of temperature , greater the current. So the curent strength can form the basis for measuring the difference in temperature. And when one of these temperatures is known, we can calculate the other.

A) Kinetic Energy | B) Weight |

C) Potential Energy | D) Impulse |

Explanation:

Rate of change of impulse equals the force . In case of freely falling body the only force is the weight.

A) Depends on their masses | B) Sphere |

C) Disk | D) Both reach at the same time |

Explanation:

Time does not depend on mass, else

=> is least for 'sphere' and

hence least time is taken by sphere.

A) 3:4 | B) 5:4 |

C) 5:1 | D) 3:2 |

Explanation:

In series : E1 + E2 = K(50)

In parallel : E1 - E2 = K(10)

E1 + E2 / E1 - E2 = 5/1

=> E1/E2 = 3/2

The emf's are in the ratio of 3:2.

A) A | B) B |

C) C | D) D |

Explanation:

To complete the vertical loop, the minimum speed required at the lowest point = .

A) Argon, copper, silver | B) Hydrogen, argon, copper |

C) Oxygen, copper, silver | D) Hydrogen, oxygen, Argon |