Answer: a boy jumping down
Answer: 60m/s
Explanation:
The wavespeed is the distance covered by the wave in one second. It is measured in metre per second, and represented by the symbol V
Wavespeed (V) = Frequency F x wavelength λ
i.e V = F λ
In the first case:
Wavespeed = 30 m/s
Frequency of sound = 6Hz
Wavelength = 5m
In the second case:
Wavespeed = ?
Frequency of sound = (2x 6Hz = 12Hz)
Wavelength = 5m (remains constant)
Apply V = F λ
Wavespeed = 12 Hz x 5m
Wavespeed = 60m/s
Therefore, when frequency is doubled, the speed is also doubled. Thus, the new speed of the wave is 60m/s
Answer:
The weight of the body, W = 793.8 m/s²
Explanation:
Given,
The volume of the body, v = 45,000 cm³
The density of the body, ρ = 1.8 g/cm³
The mass of the body is given by the formula,
m = ρ x v
= 1.8 g/cm³ x 45,000 cm³
= 81,000 g
Hence, the mass of the body is m = 81 kg
The weight of the body,
W = m x g
= 81 kg x 9.8 m/s²
= 793.8 m/s²
Hence, the weight of the body, W = 793.8 m/s²