Answer:
t = 7 sec.
Explanation:
As the car and the truck travel the same distance, assuming a constant acceleration, we can describe the movement of the truck and the car with these equations for this same displacement:
x(truck) = v*t (1)
x(car) = 
As the left sides of (1) and (2) are equal each other, the same must be true for the right sides:
v*t = 
Solving for t, replacing v= 10.5 m/s and a= 3 m/s², we have:
⇒ t = 7 sec.
<span>W=98*1.49/9.8 N
</span>soo <span>14.9 Newtons</span>
Answer:
The electromagnetic force
Explanation:
The electromagnetic force is one of the four fundamental forces of nature. Namely, they are:
- Electromagnetic force: it is the force exerted between electrically charged particles (and between magnetic fields). The force can be either attractive (if the two charges have opposite signs) or repulsive (if the two charges have same sign), and it acts over an infinite range.
- Gravitational force: it is the force exerted between objects with mass. It is always attractive, and it also has an infinite range of action. It is the weakest of the four fundamental forces.
- Strong nuclear force: it is the force that acts between protons and neutrons inside the nucleus, and it is responsible for keeping the nucleus together and preventing it from breaking apart (due to the electrostatic repulsion between protons)
- Weak nuclear force: it is the force responsible for certains nuclear decays, such as the beta decay, in which a neutron turns into a proton, emitting an electron and an antineutrino.
in china, there is a family limit for only having 1 child
at 10 billion people on earth, we will most likely run out of food supply
