At certain altitude, the temperature of air decrease, The air becomes saturated and water vapour molecules starts condensing.
As the altitude of air increase, the atmospheric pressure decrease due to which the temperature of the air decrease. The water molecules in the atmosphere start condensing, which saturate the air (that is air can no hold water molecules), due to which the water vapour molecules starts condensing and falls on the earth in the form of rain.
Momentum, p = m.v
m of the girl = 60.0 kg
m of the boat = 180 kg
v of the girl = 4.0 m/s
A) Momentum of the girl as she is diving:
p = m.v = 60.0 kg * 4.0 m/s = 24.0 N/s
B) momentum of the raft = - momentum of the girl = -24.0 N/s
C) speed of the raft
p = m.v ; v = p/m = 24.0N/s / 180 kg = -0.13 m/s [i.e. in the opposite direction of the girl's velocity]
Answer:
Explanation:
Actual weight, Wo = 5 N
Apparent weight, W = 4.5 N
density of water = 1 g/cm^3 = 1000 kg/m^3
density of gold, = 19.32 g/cm^3 = 19.32 x 1000 kg/m^3
Buoyant force = Actual weight - Apparent weight
Volume x density of water x g = 5 - 4.5
V x 1000 x 9.8 = 0.5
V = 5.1 x 10^-6 m^3
Weight of gold = Volume of gold x density of gold x gravity
W' = 5.1 x 10^-6 x 19.32 x 1000 x 9.8 = 0.966 N
As W' is less than W so, it is not pure gold.
Explanation:
The answer is in the pic above
Answer:
Explanation:
Let acceleration of fall be a .
v² = u² + 2as
v = 3.8 m /s
u = 0
s = 3.5 m
3.8² = 0 + 2 x a x 3.5
a = 2.06 m /s²
Since this acceleration is less than g , an upward force is acting on the firefighter in the form of friction . Let this force be F . Let mass of the firefighter be m .
m = 765 / 9.8
= 78.06 kg
mg - F = ma
765 - F = 78.06 x 2.06
765 - F = 160.8
F = 604.2 N .
