Answer:
39.8 °C
Explanation:
m = mass of the ice = 100 g
L = latent heat of fusion of ice = 334 Jg⁻¹
M = mass of water = 200 g
= specific heat of water = 4.2 Jg⁻¹°C⁻¹
= initial temperature of water = ?
= final temperature of water = 0 °C
Using conservation of heat
Heat gained by ice = heat lost by water
m L = M ( - )
(100) (334) = (200) (4.2) ( - 0 )
= 39.8 °C
Answer:
Explanation:
velocity of source, Vs = 114 m/s
original frequency, f = 3.65 kHz
velocity of observer , Vo = 0 m/s
velocity of sound, v = 334 m/s
let the frequency is f'.
The formula for the doppler effect is given by
where, v is the velocity of sound.
f' = 5.54 kHz
Answer:
False
Explanation:
Think about every warning on electrical products, which is 'DO NOT KEEP NEAR WATER'
I believe it is Thermal Radiation. But I’m not 100% sure.
Sorry if I’m wrong
Answer:
B
Explanation:
From Newton's law of motion, we have:
V^2 = U^2 + 2gH
Where V and U are final and initial velocity respectively.
H is the height.
For the object to have a sustain a maximum height it means the final velocity of the object is zero.
By computing the height of the object sustain by A, we have:
0^2 = 2^2 -2×10×H
0= 4 -20H
4 = 20H;
H= 0.2m
For object B we have;
0^2 = 1^2 -2×10×H
0 = 1 -20H
H = 1/20= 0.05m
From computing the height sustain by both objects, we see object B is projected at a shorter height into atmosphere than A.
Hence object B will return to the ground first.