Answer:
Around 3.57m/s
Explanation:
p=mv
Let's denote the momentum, mass, and velocity of the car with the subscript 1, and for the truck use 2. After the collision, the combined momentum can be denoted with the subscript 3.

Hope this helps!
See for yourself how the forces of electricity and magnetism can work together by building a simple DC electric motor using simple materials you can find in any hardware store!
Electricity and magnetism are both forces caused by the movement of tiny charged particles that make up atoms, the building blocks of all matter. When a wire is hooked up to a battery, current flows through the wire because negatively charged electrons flow from the negative terminal of the battery toward the positive terminal of the battery because opposite charges attract each other, while similar charges repel each other. This flow of electrons through the wire is an electric current, and it produces a magnetic field.
In a magnet, atoms are lined up so that the negatively charged electrons are all spinning in the same direction. Like an electric current, the movement of the electrons creates a magnetic force. The area around the magnet where the force is active is called a magnetic field. Metal objects and other magnets that enter this field will be pulled toward the magnet.
The way the atoms are lined up creates two different poles in the magnet, a north pole and a south pole. As with electrical charges, opposite poles attract each other, while like poles repel each other.
Learn about electromagnetism and its many uses here.
Now let's watch it work as we build a motor.
(Note: This science project requires adult supervision.)
Answer:
, repulsive
Explanation:
The magnitude of the electric force between two charged particles is given by Coulomb's law:
where:
is the Coulomb's constant
are the two charges of the two particles
r is the separation between the two charges
The force is:
- repulsive if the two charges have same sign
- Attractive if the two charges have opposite signs
In this problem, we have two electrons, so:
is the magnitude of the two electrons
is their separation
Substituting into the formula, we find the electric force between them:

And the force is repulsive, since the two electrons have same sign charge.
Answer:
The new force becomes 4 times the initial force.
Explanation:
The force of attraction or repulsion is given by the relation as follows :

Where
d is the distance between the interacting charges
F is inversely proportional to the distance between charges.
If the distance is halved, d'=(d/2), new force is given by :

So, the new force becomes 4 times the initial force.
Static friction is the friction that exists between a stationary object and the surface on which it's resting.
frictional force occurs when you try to push an object alongside a surface.