Let the mass of 2500 kg car be
and it's velocity be
and the mass of 1500 kg car be
and it's velocity be
.
After the bumping the mass be M and it's velocity be V.
By law of conservation of momentum we have

2500 * 5 + 1500 * 1=4000 * V
V = 14000/4000 = 7/2 = 3.5 m/s
So the velocity of the two-car train = 3.5 m/s
When solar radiation reaches the Earth it quickly dissipates as most of the radiation and UV rays are blocked by ozone layer, but more radiation and UV rays are able to get through because of global warming.
Answer:
a
Explanation:
when magma cools Crystal's form because the solution is super saturated with respect to some minerals if the magma cools quickly the crystals do not have much time to form hence they are small and also the resulting rock is fine grained
Using coils of fewer turns on the electromagnet
Answer:
Speed of the wave is 7.87 m/s.
Explanation:
It is given that, tapping the surface of a pan of water generates 17.5 waves per second.
We know that the number of waves per second is called the frequency of a wave.
So, f = 17.5 Hz
Wavelength of each wave,
Speed of the wave is given by :
v = 7.87 m/s
So, the speed of the wave is 7.87 m/s. Hence, this is the required solution.