Pushing a broke down car, even done by more than one person, is difficult especially if the distance to be covered is quite far. A car is heavy and it requires a lot of force to start the car moving. This is because the inertia of the car to remain at rest is great. Additionally, the force applied in pushing the car must be greater than the frictional force to cause it to accelerate. The frictional force is dependent on the mass of the object which means that the frictional force acting on the car is also great. Finally, with every push of the car, the frictional force will always be present and acting on the opposite direction. The push that will be supplied must be sustained all throughout.
Answer:
The best option is for the following option m = 15 [g] and V = 5 [cm³]
Explanation:
We have that the density of a body is defined as the ratio of mass to volume.
where:
Ro = density = 3 [g/cm³]
Now we must determine the densities with each of the given values.
<u>For m = 7 [g] and V = 2.3 [cm³]</u>
![Ro=7/2.3\\Ro=3.04 [g/cm^{3} ]](https://tex.z-dn.net/?f=Ro%3D7%2F2.3%5C%5CRo%3D3.04%20%5Bg%2Fcm%5E%7B3%7D%20%5D)
<u>For m = 10 [g] and V = 7 [cm³]</u>
<u />![Ro=10/7\\Ro=1.42[g/cm^{3} ]\\](https://tex.z-dn.net/?f=Ro%3D10%2F7%5C%5CRo%3D1.42%5Bg%2Fcm%5E%7B3%7D%20%5D%5C%5C)
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<u>For m = 15 [g] and V = 5 [cm³]</u>
<u />![Ro=15/5\\Ro=3[g/cm^{3} ]\\](https://tex.z-dn.net/?f=Ro%3D15%2F5%5C%5CRo%3D3%5Bg%2Fcm%5E%7B3%7D%20%5D%5C%5C)
<u />
<u>For m = 21 [g] and V = 8 [cm³]</u>
<u />![Ro=21/8\\Ro=2.625[g/cm^{3} ]\\](https://tex.z-dn.net/?f=Ro%3D21%2F8%5C%5CRo%3D2.625%5Bg%2Fcm%5E%7B3%7D%20%5D%5C%5C)
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Answer You need to consider that the gravity on earth is 9.8 m/s/s. This means any object you let go on the earths surface will gain 9.8 m/s of speed every second. You need to apply a force on the object in the opposite direction to avoid this acceleration. If you are pushing something up at a constant speed, you are just resisting earths acceleration. The more massive and object is, the greater force is needed to accelerate it. The equation is Force = mass*acceleration. So for a 2kg object in a 9.8 m/s/s gravity you need 2kg*9.8m/s/s = 19.6 Newtons to counteract gravity. Work or energy = force * distance. So to push with 19.6 N over a distance of 2 meters = 19.6 N*2 m = 39.2 Joules of energy. There is an equation that puts together those two equations I just used and it is E = mgh
The amount of Energy to lift an object is (mass) * (acceleration due to gravity) * (height)
:Hence, the Work done to life the mass of 2 kg to a height of 10 m is 196 J. Hope it helps❤️❤️❤️
Explanation:
Answer:
As a type of thermal power station, a coal-fired power station converts chemical energy stored in coal successively into thermal energy, mechanical energy and, finally, electrical energy. The coal is usually pulverized and then burned in a pulverized coal-fired boiler.Coal-fired plants produce electricity by burning coal in a boiler to produce steam. The steam produced, under tremendous pressure, flows into a turbine, which spins a generator to create electricity.
Contact metamorphism<span> is a type of </span>metamorphism<span> where rock minerals and texture are changed, mainly by heat, due to </span>contact<span> with magma. </span>Regional metamorphism<span> is a type of </span>metamorphism<span> where rock minerals and texture are changed by heat and pressure over a wide area or region.</span>
