Answer:2.5 m/s
37.5KJ
Explanation:
Let
be the initial velocity of rail road car ,coupled cars & Final velocity of system respectively.

Conserving momentum



Therefore Final velocity of system is 2.5m/s
(b)Mechanical Energy lost =Initial Kinetic Energy -Final Kinetic Energy



Answer:
1.) Covering the ceiling and walls with soft perforated boards
2.) Hanging curtains round the hall
3.) Having more opening in the wall.
Explanation:
This is due to what we called Reverberation due to poor acoustic properties.
Reverberation can be reduced by;
1.) Covering the ceiling and walls with soft perforated boards
2.) Hanging curtains round the hall
3.) Having more opening in the wall.
When a dielectric material is inserted between two plates of capacitor that are connected to a battery, you would observe that both the charge and the capacitance of the capacitor would change. This is due to the dielectric material which is able to transmit electric force.
Answer:
The weight of the body, W = 793.8 m/s²
Explanation:
Given,
The volume of the body, v = 45,000 cm³
The density of the body, ρ = 1.8 g/cm³
The mass of the body is given by the formula,
m = ρ x v
= 1.8 g/cm³ x 45,000 cm³
= 81,000 g
Hence, the mass of the body is m = 81 kg
The weight of the body,
W = m x g
= 81 kg x 9.8 m/s²
= 793.8 m/s²
Hence, the weight of the body, W = 793.8 m/s²
Currents of dry sinking air cause the dry conditions of earth's major deserts at: <span>30° N and 30° S Latitudes
At approximately 30 degrees from the equator, the air that moved up from the equator started to descends. This air, however, could only come from one direction. So when the air is blocked by a mountain, the other side will not receive any water that it contains. This makes the other sides of the mountain became really dry which will eventually cause the formation of the desert.</span>