1. With this statement, the author is referring to the fact that the vehicles are one of the largest polluters of the air. In order to reduce the pollution, the vehicles that are used will need to be changed, and with it the pollution will decrease significantly. The reduction of the pollution will come because the vehicles on hydrogen will not cause any pollution, so the enormous amounts of carbon dioxide released from the combustion of the engines will be thing of the past.
2. There are several challenges with this type of vehicles in order for them to replace the fossil fuel driven ones. The big price is one of the factors, as the majority of the people can not afford these cars. Another problem is that these vehicles are not as fast as the fossil fuel driven ones, and lot of people enjoy fast driving, despite it not being safe. There are millions of vehicles out there on the roads, and changing all of them with hydrogen vehicles will take a lot of time, as lot of those vehicles are new ones, so the people will not be willing to just throw them away and leave them rot in their garages. In order for the change of the driving park to be accomplished, the prices should go down, the people to be more serious about the environment and its protection, and patience as several decades will probably be needed for a change like this to be competed.
3. The fuel celled cars are a viable answer to decrease the pollution, as they are not causing any pollution, but instead will stop the process of large emissions of carbon dioxide from the fossil fueled cars. While this method is a good one, it should not be the only, as on its own it can not have the desirable effect, but instead all the major polluters should be included in the process. The industry and the production of energy are one of the major polluters as well, so they will need to follow the example, as if they not, the problem will stay, considering that the industry is constantly growing and the demand for energy is constantly growing too.
Answer:
25kg
Explanation:
The formula for acceleration due to gravity is:
Here, G represents a constant and M represents the mass of the object. We don't need to know the actual values to solve this, then: We can just multiply by the amount they are multiplied relative to earth.
Multiplying this by the weight of the person on Earth of 40kg, you get 0.625*40=25kg.
Hope this helps!
Answer:
0.73 m/s
Explanation:
From Newton second law of motion,
I = m(v-u)...................... Equation 1
Where I = Impulse, m = mass of the person, v = final velocity, u = Initial velocity.
make v the subject of the equation
v =(I/m)+u................. Equation 2
Note: u = 0 m/s as the person is falling from an height.
Given: I = 55 Ns, m = 75 kg, u = 0 m/s
Substitute into equation 2
v = 55/75
v = 0.73 m/s
1. Pressure = Force/Area
When a ballon is pressed against many pins then the area is increased as compared to when it is pressed against a single pin. The force by which the balloon is pressed remains the same. Less the area, more the pressure. So, the balloon pops when it is pressed against one pin.
2. The candle goes off when covered with a glass because for burning the candle need oxygen. When glass on placed on the candle then the oxygen supply is stopped. So, when available oxygen is finished, the candle goes off. Water rises in the glass, because when the candle is burning, it expands the air inside the glass due to its heat. But when candle wents off, the air is cooled again and it contracts. So, a vacuum is created. That's why the water rises in the glass to fill the vacuum and to balance the air pressure inside and outside the glass.
3. Objects tend to maintain their state of motion or rest unless subjected to an external force. This property is called Inertia. More the mass more the inertia. When sudden brakes are applied, then our body still tends to remain in motion. That's why our body go forward.
Explanation:
Thermal equilibrium is the state in which there is no net flow of thermal energy between two bodies in contact. This happens when, after a certain time, the temperature of both bodies is the same. Since both temperatures are the same, the heat flow is zero.
