Physics
Complete the following by choosing the correct answers from the bracket:
(a) A car is moving in uniform circular motion. The direction of friction between the tyres and the path is …………… [towards the centre / tangential to the path].
(b) When a ray of light passes from a denser to a rarer medium, its wavelength …………… [decreases / increases].
(c) The lid of a calorimeter minimises heat loss by …………… [convection / radiation].
(d) Quality of sound depends on its …………… [amplitude / waveform].
(e) A substance whose resistance becomes almost negligible at a temperature near absolute zero is called a …………… [semiconductor / superconductor].
(f) …………… radiation deviates minimum in a magnetic field [Alpha / Beta].
Answer
(a) A car is moving in uniform circular motion. The direction of friction between the tyres and the path is tangential to the path.
(b) When a ray of light passes from a denser to a rarer medium, its wavelength increases.
(c) The lid of a calorimeter minimises heat loss by convection.
(d) Quality of sound depends on its waveform.
(e) A substance whose resistance becomes almost negligible at a temperature near absolute zero is called a superconductor.
(f) Alpha radiation deviates minimum in a magnetic field.
Related Questions
Three substances A, B and C of same mass are present at their respective melting points. On heating, if they melt completely in 5 minutes, 7 minutes and 3 minutes respectively, then which substance has the highest specific latent heat?
(Assume heat is absorbed at the same rate)
- Substance A
- Substance B
- Substance C
- All the substances have same specific latent heat
An atom of lithium contains 3 electrons, 3 protons and 4 neutrons. Its mass number is:
- 3
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State two factors on which the position of Center of Gravity of a body depends.
Case 1: Lata cuts a potato into two halves, using a cutter which belongs to a Class II lever. She needed effort E1.
Case 2: Then she cuts one half of this potato again, but this time she needed effort E2. If E1 > E2 then:
(a) In which case (1st or 2nd) was the potato closer to her hand applying the effort? (Assume normal reaction of the surface of the potato is same in both cases)
(b) Give a reason for your answer in (a) above.