Answer:

Explanation:
Given,
mass of the object,m = 0.30 Kg
initial speed, v_i = 3 m/s
time of collision = 0.20 s
final speed, v_f = -4 m/s
Impulse = change in momentum



Hence, impulse of the object is equal to 
Answer:
B. 25 feet
Explanation:
In most cities in US, passenger car brakes must stop a car moving at 20 miles per hour at 25 feet.
Therefore, the correct option is "B" 25 feet
Answer:
water flows easier in the mountains because there is less air pressure.
Answer:
Very hot during the day and very cold at night.
Explanation:
Due to the thin atmosphere, they have very hot climate during the day time and very cold climate at night. This happens because they contain very low amounts of greenhouse gases. These gases retain the heat at night. The atmosphere also prevents excessive light and UV rays from entering. The thin atmosphere leads to many asteroids and comets hitting the surface of the planet. On earth, these asteroids usually, burn up in the mesosphere layer of the atmosphere. These asteroid collisions cause massive fires. This in turn, causes the temperature to increase during the day. During the night time, massive fires cannot burn due to the low temperature because of the lack of greenhouse gases.
Answer:
Explanation:
This problem relates to interference of light in thin films .
The condition of bright fringe in thin films which is sandwitched by two layers of medium having lesser refractive index is as follows.
2nt = (2n+1) λ / 2 , n is refractive index of thin layer , t is its thickness , λ is wavelength of light .
2 x 1.5 t = λ / 2 , if n = 0 for minimum thickness.
2 x 1.5 t = 600 / 2 nm
t = 100 nm .