1. Renewable energy is energy that comes from sources that are replenished naturally and can be used again and again. Examples include solar, wind, hydro, geothermal, and biomass energy. Non-renewable energy, on the other hand, comes from sources that will eventually run out or take millions of years to replenish, such as fossil fuels like oil, coal, and natural gas.
2. Gravitational force is the force of attraction that exists between any two objects in the universe. It is the force that pulls objects towards each other and is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
3. The force acting on a body of mass 45kg accelerating at 5m/s2 can be calculated using the formula:
Force = Mass x Acceleration
Force = 45kg x 5m/s2
Force = 225 N (Newtons)
Therefore, the force acting on the body is 225 N.
4. Four planets are:
- Mercury
- Venus
- Earth
- Mars
5. Two advantages of renewable energy are:
- Renewable energy sources are clean and do not produce harmful pollutants or greenhouse gases that contribute to climate change and air pollution. This makes them better for the environment and human health.
- Renewable energy sources are sustainable and will never run out. They are also becoming more affordable and accessible as technology improves, making them a viable alternative to non-renewable energy sources.
Hope this helped!