Answer:
<em>765,000 Joule</em>
Explanation:
<u>Principle of Conservation of Energy
</u>
The total energy in an isolated system cannot be created or destroyed, but transformed. Moving objects have kinetic energy, objects placed in some height above a reference level have gravitational potential energy. When they change their motion variables, one energy converts into the other, but if the numbers don't fit, we know there was some other type of energy acting into the system. The most common reason for energy 'losses' is the thermal energy, produced when objects move in rough surfaces or take friction from the air.
The 7,500 kg truck is originally traveling at 20 m/s to a certain height we'll set to 0. Thus, its total energy is
When it comes to a stop, its speed is 0 and its height is 10 m higher than before. It means all the kinetic energy was transformed into other types of energy. The gravitational potential energy is
Since this number is not equal to the previous value of the energy, the difference is due to thermal energy dissipated by friction
acceleration of rocket is given here as
now we know that
now integrating both sides
here since its given that rocket will accelerate for t = 10 s
so here we have
so after t = 10 s the speed of rocket will be 130 m/s upwards
Potential energy at any point is (M G H). On the way down, only H changes. So halfway down, half of the potential energy remains, and the other half has turned to kinetic energy. Half of the (M G H) it had at the tpp is (0.5 x 9.8 x 10) = 49 joules.
Answer:
<h3>0.99 m</h3>
Explanation:
Average velocity is the change of rate of displacement with respect to time;
Average velocity = Displacement/Time
Given
Average velocity of the frog = 1.8m/s
Time = 0.55s
Required
Displacement of the frog
Substitute the given parameters into the formula;
1.8 = displacement/0.55
cross multiply
Displacement = 1.8*0.55
Displacement = 0.99 m
Hence the frog's displacement is 0.99m
Answer:
Smaller refractive power
Explanation:
The refractive power of an eye is the extent to which it can converge or diverge the light rays.
Near point is the the closest point for an eye such that when an object is placed at that point the image it forms is sharp and clearly visible to the eye.
A the person ages, the ciliary muscles of the eyes weakens and as a result the lens contracts and the formation of the image takes place behind the retina instead of forming at the retina.
Thus the near point also increases and the refractive power becomes smaller.
