Physics - Study Mode

[#1341] Who among the following developed the technology of underground nuclear explosion ?
Correct Answer

(A) Dr. Homi J. Bhabha

Explanation

Solution: Homi Jehangir Bhabha was an Indian nuclear physicist, founding director, and professor of physics at the Tata Institute of Fundamental Research. Colloquially known as “father of Indian nuclear programme,” Bhabha gained international prominence after deriving a correct expression for the probability of scattering positrons by electrons, a process now known as Bhabha scattering. His major contribution included his work on Compton scattering, R process, and furthermore the advancement of nuclear physics. He was awarded Padma Bhushan by Government of India in 1954.

[#1342] A radioactive substance does not undergo any change (in mass or charge) during
Correct Answer

(A) Gamma-emission

Explanation

Solution: Gamma-rays do not carry any charge. These rays do not have any mass and hence can not be considered to be made up of particles.

[#1343] The wall of a dam is broader at the base
Correct Answer

(B) To withstand pressure that increases with depth

Explanation

Solution: The pressure applied to walls of the dam will be a function of the amount of water that is over that particular point on the wall. So water pressure is very large at the bottom due to its large depth. That's why dams are constructed thicker at their bottoms than at their tops.

[#1344] It is easy to burst a gas-filled balloon with a needle than with a nail. It is because
Correct Answer

(C) Needle exerts more pressure than nail on the balloon.

Explanation

Solution: It is easy to burst a gas filled balloon with a needle than with a nail. It is because needle exerts more pressure on the bottom.

[#1345] The force exerted on an object is 200 N and its mass is 100 kg. Find the acceleration of the object.
Correct Answer

(C) 2 m/sq.s