An area where the particles in a medium are spaced close together is called compression.
1. For better aerodynamics and easier air flow while flying.
2. Because we generate friction that lights a match
4. Without friction we couldnt walk(we would slip around like on ice), cars wouldnt stick on road while driving.
3. Grooves in the tyres are designed to allow water to be expelled from beneath the tire and prevent hydroplaning.
Answer:
PE=0.29J
Explanation:
According to the description, there is a angle and in point swung upward of 70°
So,
Appling the equation of Potential Energy we have,