Answer:
No, it does not violate Newton's first law
Explanation:
Newton's first law of motion states that, "A body will continue in its state of rest or uniform motion in a straight unless acted up by a force to make it act otherwise" This means a force is required to initiate movement and also required to halt it.
For a skate positioned to roll down a bank, Here, the force of gravity acting on the skate acting downward will make the skate roll without having to push off the skate with a foot. Because the position of the skate doesn't balance the Gravitational force acting on it. Hence. The Gravitational force is enough to set the skate in motion.
Answer:
3 seconds to reach maximum height
3.61 seconds to go from maximum height to the ground
6.61 seconds for the whole thing
Explanation:
Since the question states the stone is thrown vertically we can neglect using trigonometry for component vectors and can just use the given values.
At the top of the arc the velocity will instantaneously be at zero, therefore the final velocity for this is 0.
Since we know final velocity(Vf) , initial velocity(V0), and acceleration(a) we can find the time(t) using this equation:
Vf = V0 + at
0 = 30 + (-10)t
t = 3 seconds
*acceleration is negative in this case because we assume that acceleration due to gravity is positive when acting downwards. in this case since the gravitational force is acting against the object the acceleration due to gravity is negative
Next: to find total time I am going to find the total distance it needs to travel to get down to the ground by adding the distance it traveled upward to the height of the tower
the distance traveled upward can be found using this equation:
Vf^2 = V0^2 + 2ad
0^2 = 30^2 + 2(10)d
d = 45m
Then add 45m to the height of the tower(20m) to get 65m total distance = 65m
Now I can find total time needed by plugging into this equation:
d = V0*t + (1/2)a*t^2
*note that since we are starting from the maximum height now: V0 = 0
65 = 0*t + (1/2)(10)t^2
65 = 5t^2
t = 3.61 seconds
Answer:
The frequency of the wave is 5.0Hz
Explanation:
The frequency of a wave is the number of oscillations or revolutions made in a second.
if it is heat flow through a metal, it would be necessary to have a conductor so that the electrons can flow through it (delocalised electrons).
In terms of radiation, it would require a good absorber of heat (e.g. a black surface) so that the thermal energy flows through on the surface area.
Answer:
Gamma radiation or Cathode rays
Explanation:
by striking incident gamma or cathode rays onto the solid when placed on a photographic plate