Question Detail

Scalar Quantities are

physical quantities which have magnitude only and no direction
physical quantities which have no magnitude only and only direction
physical quantities which have magnitude only and direction
physical quantities which have no magnitude and no direction

Answer: Option A

1. David Hughes invented

Machine Gun
Microphone
Microscope
Motorcycle

Answer: Option B

Explanation:

David Hughes of USA invented Microphone in 1878,

Machine Gun was invented by Richard Gatling of USA in 1861,

Microscope was invented by Z. Jansen of Netherlands in 1590,

Motorcycle was invented by Edward Butler of England in 1884.

2. Harry Brearley has invented

Electric iron
Electromagent
Stainless Steel
Gramophone

Answer: Option C

Explanation:

Harry Brearley of England has invented Stainless Steel in 1913,

Electric iron has been invented by H.W. Seeley of USA in 1882,

Electromagent has been invented by W.Sturgeon of England in 1824,

Gramophone has been invented by T.A. Edison of USA in 1878.

3. Electric Motor converts

Electrical energy into mechanical energy
Mechanical energy into Electrical energy
Electrical energy into light energy
None of above

Answer: Option A

4. Solar cell converts

Sound energy into electrical energy
Electrical energy into mechanical energy
Solar energy into electrical energy
Electrical energy into light energy

Answer: Option C

5. Thomas Alva Edison invented

Cinema
Cine Camera
Computer
Cinematograph

Answer: Option D

Explanation:

Thomas Alva Edison of USA invented Cinematograph in 1891,

Cinema was invented by A.L. and J.L. Lumiere of France in 1895,

Cine Camera was invented by Friese-Greene of Britain in 1889,

Computer was invented by Charles Babbage of Britain in 1834, he is also known as Father of Computer.