Answer:
857.5 m
2.8583×10⁻⁶ seconds
Explanation:
Time taken by the sound of the thunder to reach the student = 2.5 s
Speed of sound in air is 343 m/s
Speed of light is 3×10⁸ m/s
Distance travelled by the sound = Time taken by the sound × Speed of sound in air
⇒Distance travelled by the sound = 2.5×343 = 857.5 m
⇒Distance travelled by the sound = 857.5 m
Time taken by light = Distance the light travelled / Speed of light

Time taken by light = 2.8583×10⁻⁶ seconds
Answer:
a) V = 195.70 m/s
b) f=3.02 × 10⁻⁴ Hz
c) T = 3311.25 seconds
Explanation:
Given:
Wavelength, λ = 646 Km = 646000 m
Distance traveled = 3410 Km = 3410000 m
Time = 4.84 h = 4.84 × 3600 s = 17424 seconds
a) The speed (V) of the wave is given as
V = distance / time
V = 3410000 m/ 17424 seconds
or
V = 195.70 m/s
b) The frequency (f) of the wave is given as:
f = V / λ
f= 195.70 / 646000
f=3.02 × 10⁻⁴ Hz
c) The time period (T) is given as:
T = 1/ f
T = 1/ (3.02 × 10⁻⁴) Hz
T = 3311.25 seconds