Since momentum is a vector quantity, take any direction as positive and other as negative. Answer won't change.
The answer would be B..
Since sand can heat up quickly, it will also cool off quickly. But water takes a long time to heat up and cool down.
Answer:
the acceleration of harry is equal to 66.126 m/s²
Explanation:
given,
harry is 35 m behind Draco
speed of Draco = 40 m/s
original speed of harry = 50 m/s
acceleration = ?
time taken by the Draco
t =
t = 1.875 s
distance covered by Harry
d = 35 + 175 = 210 m
to calculate the acceleration of harry


a × 3.516 × 0.5 = 116.25
a = 66.126 m/s²
hence, the acceleration of harry is equal to 66.126 m/s²
Answer:
r₂ = 0.2 m
Explanation:
given,
distance = 20 m
sound of average whisper = 30 dB
distance moved closer = ?
new frequency = 80 dB
using formula

I₀ = 10⁻¹² W/m²
now,



to hear the whisper sound = 80 dB



we know intensity of sound is inversely proportional to square of distances



r₂ = 0.2 m
High frequency , it is because wavelength is inversely proportional to frequency