Given
Car 1
m1 = 1300 kg
v1 = 20 m/s
m2 = 900 kg
v2 = -15 m/s
(Negative sign shows that direction of car 2 is opposite to car 1)
Procedure
As per the conservation of linear momentum, "The total momentum of the system before the collision must be equal to the total momentum after the collision". And this applies to the perfectly inelastic collision as well. Then the expression is,
Thus, we can conclude that the speed and direction of the cars after the impact is 5.68 m/s towards the first car.
Least count of the pulse stopwatch is given by
this means each division of the stopwatch will measure 0.1 s of time
After 3 journeys from one end to other we can see that total time that is measured here is shown by the clock as 52nd division
So here total time is given as
Time = (Number of division) (Least count)
now we will have
Answer:
B) The cosmic background radiation is expected to contain spectral lines of hydrogen and helium, and it does.
Explanation:
Infrared is created by detecting the produced radiation coming off of clouds. The temperature of the cloud will define the wavelength of radiation produced from the cloud. The benefit of the infrared imagery is that can be used day and night to conclude the temperature of the cloud tops and earth surface structures and to get the general idea of how clouds are. Based on the general guidelines to define cloud features, if the cloud is bright white on infrared then it is a high cloud or has a cloud top that is developed high into the troposphere. In this way infrared images actually display patterns of temperature on a gray scale such that at one extreme dark gray is warm and at the other extreme bright white is cold. A color scale is used to portray temperature and some improved infrared images show two or more gray scale sequences. High cold clouds are brighter white than low warm clouds.
