3. Q: Who invented telephone?

Ans: Alexander Graham Bell invented telephone.

4. Q: Who invented mobile phone?

Ans: Martin Cooper invented mobile phone.

5. Q: Who invented aeroplane?

Ans: Wilbur Wright and Orville Wright (Wright Brothers) invented aeroplane.

6. Q: Who invented helicopter?

Ans: Igor Sikorsky invented helicopter.

7. Q: Who invented motorcycle?

Ans: G. Daimler invented motorcycle.

8. Q: Who invented clock?

Ans: C. Huygens invented clock.

9. Q: Who invented light bulb?

Ans: Thomas Alva Edison invented light bulb.

10. Q: Who discovered X-ray?

Ans: W.C. Rontgen discovered X-ray.