Answer:
a) Yes because spiderman isn’t part of the system (the train), so he exerts an external force on the system, causing it to slow. The sign is negative because the train is slowing negative.
b) The train was initially moving, so it had kinetic energy, the energy of movement. There isn’t the same amount anymore because spiderman did work onto the train. Work is defined by the change of kinetic energy of the system, so the train didn’t have the same amount of that type of energy at the end.
I hope this helps! :)
Answer:
175s
Explanation:
time it takes sunlight to reach the earth in vacuum
C=light speed=299792458m/s
X=1.5x10^8km=1.5x10^11m
c=X/t
T1=X/c
T1=1.5X10^11/299792458=500.34s
time it takes sunlight to reach the earth in water:
First we calculate the speed of light in water taking into account the refractive index
Cw=299792458m/s/1.349=222233104.5m/s
T2=1.5x10^11/222233104.5m/s=675s
additional time it would take for the light to reach the earth
ΔT=T2-T1=675-500=175s
Answer: 21965.517 Pa
Explanation:
Pressure 
is the force 
exerted by a gas, a liquid or a solid on a surface (or area) 
, its unit is Pascal 
which is equal to 
and its formula is:
(1)
In this case we have the surface of a sole of a tennis shoe:
(2)
And the mass 
of the person who wears it:
On the other hand, we know the weight is the force the Earth exerts on people and objects due gravity 
:
(3)
Substituting (2) and (3) in (1):
(4)
Finally:
This is the pressure the shoe exert on the ground
White dwarfs<span> are formed from the collapse of low mass </span>stars<span>, less than about 10 time the mass of the Sun. This </span>star<span> loses most of its mass in a wind, leaving behind a core that is less than 1.44 solar mass. On the other hand,</span>neutron stars<span> are formed in the catastrophic collapse of the core of a massive </span>star.
Answer:
The ball exerts a force of 400 N on the bat.
Explanation:
Given that,
A baseball player hits a ball with 400 N of force.
We need to find the force the ball exert on the bat.
We know that,
According to Newton's third law, when object 1 exerts a force on an object 2, then object 2 will exert a force on object 1 but in opposite direction.
So, the ball exerts a force of 400 N on the bat.
