Friction is the resistance offered against the motion of one surface over the other. This is because, at the microscopic level, each surface has hills and valleys i.e. the surfaces are not completely smooth and hence the roughness of one surface locks over the other and restricts its motion. There are two kinds of friction: static friction and kinetic friction. When the object is at rest, static friction acts. While the object is in motion, kinetic friction acts. Static friction is greater than the kinetic friction because a larger force is required to change the state of rest to motion. You must have experienced that if you do not accelerate the bike while its in motion, it would slow down and eventually stop. In order to get the bike moving, initially static friction must be overcome and thereafter, kinetic friction to make it stay in motion.
From the equestion:
I=V÷R
I=20÷100
I=0.2A
That all depends on your distance from the center of each planet.
On the surface of Jupiter, the acceleration of gravity is 2.53 times
its value on the surface of the Earth.
Answer:
K_b = 78 J
Explanation:
For this exercise we can use the conservation of energy relations
starting point. Lowest of the trajectory
Em₀ = K = ½ mv²
final point. When it is at tea = 50º
Em_f = K + U
Em_f = ½ m v_b² + m g h
where h is the height from the lowest point
h = L - L cos 50
Em_f = ½ m v_b² + mg L (1 - cos50)
energy be conserve
Em₀ = Em_f
½ mv² = ½ m v_b² + mg L (1 - cos50)
K_b = ½ m v_b² + mg L (1 - cos50)
let's calculate
K_b = ½ 2.0 6.0² + 2.0 9.8 6.0 (1 - cos50)
K_b = 36 +42.0
K_b = 78 J
I think it’s the third one, if not it’s the first.