Answer:
D, using a spring scale to exert a force on the block. Measure the acceleration of the block and the applied force
Explanation:
For this you would use the net force equation acceleration=net force * mass however you will want to isolate mass so it would be acceleration/ net force to get mass. Then process of elimination comes to play.
Answer:
reduced
Explanation:
The use of bearing surfaces that are themselves sacrificial, such as low shear materials, of which lead/copper journal bearings are an example
Force = (mass) x (acceleration)
Force = (18 kg) x (3 m/s²) = 54 newtons
As long as you continue pushing the cart with 54 newtons of force,
it will accelerate at 3 m/s².
At the instant you release it, or keep your hands on it but stop pushing,
it will stop accelerating. It'll continue forward at the speed it had when
the 54 newtons of force stopped.
Answer:
d) The 2 athletes reach the same height, because the athletes run with the same speed.
Explanation:
In the whole process , kinetic energy is converted into potential energy .
1/2 m v² = mgh
v² = 2gh
h = v² / 2g
In this expression we see that height attained does not depend upon mass of the object . At the same time it also makes it clear that it depends upon velocity . As the velocity in both the cases are same , height attained by both of them will be same. Hence option d ) is correct.
Answer:
Powerful electromagnets are fitted on top of guideways either ttract or repel the magents fitted on the bottom of train. The froce of attraction/repulsion rasies the train in hovering position.
Explanation:
Magentic fields exist between two opposite/like poles. The poles do not have to be touching each other. They can be separated by a distance in a medium that doesn' block magnetic field.
In magelv train the magnetic forces between two poles are used to operate the train. The two poles are separated by train body and air.