Velocity = (distance covered in a direction) / (time to cover the distance)
Since the y-axis is position (distance), the speed at 3 seconds is the slope of the graph at 3 seconds, and NOT its y-value.
The slope is fairly easy to pick off, because the graph is so straight from 2 sec to 5 sec. During that time, the distance shrinks by 10 meters (from 10m to zero). So the slope of that whole piece of the graph is (-10m) / (3 sec).
That's a slope of (10/3 m/s) or 3.33 m/s .
In answer to the question, we can only give the speed at 3 sec, not the velocity, since we have no information about the direction of the motion. Consequently, I would call the speed a positive number. But it's not worth arguing about, so you should just select <em>choice-A </em>and not make a big scene.
Answer:
3,150,000N
Explanation:
According to Newton's second law;
F = mass * acceleration
Given
Mass = 45000kg
acceleration = 70m/s^2
Substitute
F = 45000 * 70
F = 3,150,000N
Hence the force required to be produced by the rocket engines is 3,150,000N
Answer:
Gravitational potential energy
Explanation:
Hydroelectric dams are the power plants which generates electricity by using the energy of falling water from a great height.
A the water is stored in big reservoirs and at a great height, it contain lot of potential energy due to the height. As it falls downwards, the potential energy is converted into kinetic energy of the water. this kinetic energy of the falling water is used to run the turbine, and then the electric energy is generated.
So, in hydroelectric power stations, the potential energy of water is converted into the electric energy.
5.5 s
Explanation:
The time it takes for the ball to reach its maximum height can be calculated using
since 
at the top of its trajectory. Plugging in the numbers,
