Answer:
21.8 m/s
Explanation:
At the top of the hill (crest), there are two forces acting on the motorcycle:
- The reaction force of the road, N (upward)
- The force of gravity, mg (downward)
Since the motorcycle is moving by circular motion, the resultant of these forces will give the centripetal force, so:

where the direction of the weight (mg) is equal to that of the centripetal force, and where
m is the mass of the cycle
g = 9.8 m/s^2 is the acceleration of gravity
v is the speed
r = 48.6 is the radius of the hill
The cycle loses contact with the road when the reaction force becomes zero:
N = 0
Substituting into the equation, we therefore find the maximum speed that is allowed for the cycle before losing constact:

Answer:
a = 12 [m/s²]
Explanation:
To solve this problem we must use Newton's second law which tells us that the sum of forces on a body is equal to the product of mass by acceleration.
ΣF = m*a
where:
ΣF = sum of forces acting on a body [N] (units of Newtons)
m = mass = 0.5 [kg]
a = acceleration [m/s²]
Let's take the direction of positive forces to the right and negative forces directed to the left
2 + 8 - 4 = 0.5*a
6 = 0.5*a
a = 12 [m/s²]
Answer:

Explanation:
Given,
The angle of the slide=
The mass of the child is= m
coefficient of friction = 0.20
when she slides down now apply Newton's law


therefore the acceleration

![a=g[\sin \theta -\mu \cos \theta]](https://tex.z-dn.net/?f=a%3Dg%5B%5Csin%20%5Ctheta%20-%5Cmu%20%5Ccos%20%5Ctheta%5D)
![a=9.8\times [\sin 42^\circ -0.2\times \cos 42^\circ]](https://tex.z-dn.net/?f=a%3D9.8%5Ctimes%20%5B%5Csin%2042%5E%5Ccirc%20-0.2%5Ctimes%20%5Ccos%2042%5E%5Ccirc%5D)

hence, the magnitude of acceleration during her sliding is equal to 
Answer:
Essentials. A battery is a device that stores chemical energy and converts it to electrical energy. The chemical reactions in a battery involve the flow of electrons from one material (electrode) to another, through an external circuit. The flow of electrons provides an electric current that can be used to do work.