First, we must find the vertical distance traveled upwards by the ball due to the throw. For this, we will use the formula:
2as = v² - u²
Because the final velocity v is 0 in such cases
s = -u²/2a; because both u and a are downwards, the negative sign cancels
s = 14.5² / 2*9.81
s = 10.72 meters
Next, to find the time taken to reach the ground, we need the height above the ground. This is:
45 + 10.72 = 55.72 m
We will use the formula
s = ut + 0.5at²
to find the time taken with the initial velocity u = 0.
55.72 = 0.5 * 9.81 * t²
t = 3.37 seconds
There are no statements that describe the Curies' work well on the list of choices you provided.
(And their name was "Curie", not "Cutie".)
Answer:
The work done is twice as great for block B because it is moved twice the ... Equal forces are used to move blocks A and B across the floor. ... Does the normal force of the floor pushing upward on the block do any work? ... Suppose that the mass is halfway between one of the extreme points of its motion and the center point.
Explanation:
Answer: 34%
Explanation: eff = (Eout/Ein) *100(for % form)
1200/3500 * 100 = 34%
Answer:
Momentum is always conserved, and kinetic energy may be conserved.
Explanation:
For an object moving on a horizontal, frictionless surface which makes a glancing collision with another object initially at rest on the surface, the type of collision experienced by this objects can either be elastic or an inelastic collision depending on whether the object sticks together after collision or separates and move with a common velocity after collision.
If the body separates and move with a common velocity after collision, the collision is elastic but if they sticks together after collision, the collision is inelastic.
Either ways the momentum of the bodies are always conserved since they will always move with a common velocity after collision but their kinetic energy may or may not be conserved after collision, it all depends whether they separates or stick together after collision and since we are not told in question whether or not they separate, we can conclude that their kinetic energy "may" be conserved.