Answer:
The ice melts mass is:

Explanation:
Kinetic Energy



Heat gained by ice= mass(g) x 80 cal
( 1 cal = 4.184 *10^7er or g cm^2/ sec^2)
Assuming no loss in heat, in the motion so both continue with temperature 0~C
To find so the mass (gm) of ice melted


Answer:
8.13secs
Explanation:
From the question weal are given
Height H =324m
Required
time it takes to drop t
Using the equation of motion
H = ut + 1/2gt²
Substitute the given values
324 = 0(t)+1/2(9.8)t²
324 = 1/2(9.8)t²
324 = 4.9t²
t² =324/4.9
t² = 66.12
t = √66.12
t = 8.13secs
Hence the time taken to drop is 8.13secs
Answer:
Intensity, 
Explanation:
Power of the light bulb, P = 40 W
Distance from screen, r = 1.7 m
Let I is the intensity of light incident on the screen. The power acting per unit area is called the intensity of the light. Its formula is given by :




So, the intensity of light is
.
Answer:
Explanation:
Given
time taken 
Speed acquired in 2 sec 
Here initial velocity is zero 
acceleration is the rate of change of velocity in a given time


Distance travel in this time

where
s=displacement
u=initial velocity
a=acceleration
t=time


so Jet Plane travels a distance of 42 m in 2 s
The initial speed of car A is 15.18 m/s.
Momentum is defined as mass in motion. If there are two objects (the two objects in motion or only one object in motion and the other in stationary) that collide and no other forces work in the system, the law of momentum conservation applies in the system.
p=p'
pa+pb = pa'+pb'
(ma×va) + (mb×vb) = (ma×va') + (mb×vb')
- ma = mass of object A (kg) = 1,783 kg
- mb = mass of object B (kg) = 1,600 kg
- va = speed of object A before collides (m/s)
- va' = speed of object A after collides (m/s) = 8 m/s
- vb = speed of object B before collides (m/s) = 0 m/s
- vb' = speed of object B after collides (m/s) = 8 m/s
- p = momentum before collision (Ns)
- p' = momentum after collision (Ns)
(ma×va) + (mb×vb) = (ma×va') + (mb×vb')
(1,783×va) + (1,600×0) = (1,783×8) + (1,600×8)
(1,783×va) + 0 = 14,264+12,800
(1,783×va) = 27,064

va = 15.18 m/s
Learn more about The law of momentum conservation here: brainly.com/question/7538238
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