Answer:
20 [N], in the opposite direction of the first force.
Explanation:
We know that newton's second law stipulates that the sum of forces on a body must be equal to the product of mass by acceleration.
![SumF = m*a\\30 + F = 2*5\\F = 30 - (2*5)\\F = - 20 [N]](https://tex.z-dn.net/?f=SumF%20%3D%20m%2Aa%5C%5C30%20%2B%20F%20%3D%202%2A5%5C%5CF%20%3D%2030%20-%20%282%2A5%29%5C%5CF%20%3D%20-%2020%20%5BN%5D)
The negative sign means that the other force acting on the body must be in the opposite direction to the force of 30 [N]
Answer:
fixed pulley: A pulley system in which the pulley is attached to a fixed point and the rope is attached to the object. ... movable pulley: A pulley system in which the pulley is attached to the object; one end of the rope is attached to a fixed point and the other end of the rope is free.
Explanation:
Infrared waves. The other 3 would hurt you because they are below the UV scale of 400 nanometers. Infrared is light that wouldn't harm you
Answer:
F = 69.5 [N]
Explanation:
We must remember that the friction force is defined as the product of the normal force by the coefficient of friction, and it can be calculated by the following expression.

where:
N = normal force [N]
miu = friction coefficient
f = friction force = 22 [N]
Now we must calculate the force exerted by means of Newton's second law which tells us that the sum of forces on a body is equal to the product of mass by acceleration.

where:
F = force exerted [N]
f = friction force [N]
m = mass = 95 [kg]
a = acceleration = 0.5 [m/s²]
Now replacing:
![F - 22 = 95*0.5\\F = 47.5 + 22\\F = 69.5 [N]](https://tex.z-dn.net/?f=F%20-%2022%20%3D%2095%2A0.5%5C%5CF%20%3D%2047.5%20%2B%2022%5C%5CF%20%3D%2069.5%20%5BN%5D)
The electric force acting on the charge is given by the charge multiplied by the electric field intensity:

where in our problem

and

, so the force is

The initial kinetic energy of the particle is zero (because it is at rest), so its final kinetic energy corresponds to the work done by the electric force for a distance of x=4 m: