Explanation:
The speed of a wave is given by :
......(1)
(i) Here, the wavelength of a sound wave in air reduces by a factor of 3. Equation (1) becomes :
Wavelength and frequency are inversely proportional to each other. So, if wavelength of a sound wave in air reduces by a factor of 3, then the frequency will increases by a factor of 3.
(ii) It remains the same.
Answer:
True
Explanation:
The atomic mass of oxygen is 16amu, which means the <em>molar mass</em>, the mass of one mole of oxygen atoms (1 mole = 6.02x10²³), is 16g.
James E. Hansen studied climate change
Answer:
acceleration, a = 9.8 m/s²
Explanation:
'A ball is dropped from the top of a building' indicates that the initial velocity of the ball is zero.
u = 0 m/s
After 2 seconds, velocity of the ball is 19.6 m/s.
t = 2s, v = 19.6 m/s
Using
v = u + at
19.6 = 0 + 2a
a = 9.8 m/s²