Answer:

Explanation:
speed of bat = 6 m/s
sound wave frequency emitted by bat = 30.0 kHz
as we know,
speed of sound (c)= 343 m/s



now frequency received by bat is equal to



hence the frequency hear by bat will be 29.98 Hz
Answer:
It increases to three times it's original value.
Explanation:
B
Answer:
Q=1670J
Explanation:
Mass of ice: m=5g=0.005kg
Latent heat: lambda=3.34×10⁵J/kg
Heat received by ice: Q=m×lambda
Q=0.005×3.34×10⁵=5×334=1670J
Answer:
Option B
Explanation:
The butter forms a new arrangement of atoms i.e from solid to liquid
Answer:
4200 Joules
Explanation:
Work done =force x distance
From the question , we’re given f =350N ,
d = 12m
Using the above formula, we have
Workdone = 350 x 12
= 4200 Joules