Answer:
Explanation:
Change in car's momentum = 700 * [4.5 - {-29)] = 23,450 kgm/s
A diver having mass m climbs up the diving board.
We know that Gravitational potential energy is given as <span>P<span>EG</span>=mgΔh</span>
What changes is his Gravitational potential energy due to change of height <span>Δh</span> with reference to the ground/water level.
While standing on the diving board his velocity is zero. As such kinetic energy is also zero.
Once he jumps off the springboard we see he gets additional energy from the springboard and falls down under action of gravity g. Due to decrease of height above the ground level Gravitational potential energy decreases and gets converted in to his kinetic energy. <span>1/2m<span>v2</span></span>.
While in air he encounters air resistance. Some of his energy is spent in overcoming this resistance. Gets converted in to kinetic and thermal energy of surrounding air and his body.
Once diver reaches the water, we see water splashing and hear noise of splash. Thereafter the diver comes to rest. Now his potential energy becomes zero. And converted kinetic energy has been converted in to kinetic energy, heat energy and sound energy of water.
As such energy transformation equation looks like
<span><span>Gravitational PE+Elastic PE of springboard</span><span>→Kinetic energy of air and water+Sound energy of splash+thermal energy</span></span>
Relative density is defined as:
dr = ds / dw
where:
dr: relative density
ds: density of the substance.
dw: density of water.
In this case we have the relative density of oak wood:
dr = 0.64.
We want to find the density of the substance: ds
Therefore we need to know the density of water in the cgs unit system:
dw = 1g / c ^ 3
Finally:
ds = dr * dw
ds = 0.64 * 1 g / cm ^ 3
ds = 0.64 g / c ^ 3
The density of the oak wood in cgs is 0.64 g / cm ^ 3
Velocity and acceleration are vector quantities whereas speed, temperature and age are not.
<h3>What is a vector quantity?</h3>
Vector is a quantity that has both magnitude and direction and is represented by an arrow whose direction is same as that of the quantity and length is proportional to the quantity's magnitude.
Vector has magnitude and direction but it does not have position. Velocity and acceleration both are vector quantities as they have magnitude and direction.
If the speed of an object remains same but direction changes then the object is accelerating. It is important to remember that acceleration and velocity aren't always in the same direction.
To know more about vector quantity, refer
brainly.com/question/626479
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