Dark energy is what is causing the accelerating expansion of the universe. It can also be defined as the theoretical energy that counteracts or acts against gravity. Others also define it as a theoretical, new kind of dynamic energy field that fills space, but whose energy has an effect opposite to that of normal energy.
<span>Since the trains area headed in completely opposite directions, the rate at which they gain distance from each other is simply equal to the sum of the magnitudes of their velocities, in this case 85 + 75 = 160 miles per hour. Therefore, the amount of time it will take for them to be 352 miles apart is 352/160 = 2.2 hours, or 2 hours and 12 minutes.</span>
Answer:
b. it has the same centripetal acceleration as car A.
Explanation:
According to the question, the data provided is as follows
Constant speed of car A = 20 m/s
Constant tangential acceleration until its speed is 40 m/s
Based on the above information, the true statement is the same centripetal acceleration as car A because
As we know that
Centripetal acceleration is
where,
= velocity
r = radius of the path
Now if both car A and car B moving in the same or identical circular path having the same velocity so in this case there is the same centripetal acceleration for that particular time
hence, the second option is correct
Electrostatic force arises due the charges at rest.In a isolated atom there is three fundamental particles called electron,proton and neutron.the electron is negatively charged,proton is positively charged and the neutron is neutral.
Generally the force between electron and proton is attractive,there will be also repulsion between proton and proton.due to the strong nuclear forces atom main its stability In an stable atom the the neutron to proton ratio lies between 1 to 1.42.if the number of neutrons are increased more,the stability will be hampered resulting the decrease in nuclear force also.
As neutron is neutral,there will be no change in the electrostatic forces as there is no increment of charge.but when the neutron number is increased at that time the binding energy per nucleon is decreased which in turn affects the nuclear force which is a short range force.the nucleus becomes heavy and unstable which undergoes decay.
one thing we have to remember also that the nuclear force is spin dependent .so the change in neutron number affects the strong nuclear force which is the reason for its decrement.
Answer:
≈ 6.68 m/s
Explanation:
A suitable formula is ...
vf^2 -vi^2 = 2ad
where vi and vf are the initial and final velocities, a is the acceleration, and d is the distance covered.
We note that if the initial launch direction is upward, the velocity of the ball when it comes back to its initial position is the same speed, but in the downward direction. Hence the problem is no different than if the ball were initially launched downward.
Then ...
vf = √(2ad +vi^2) = √(2·9.8 m/s^2·1.0 m+(5 m/s)^2) = √44.6 m/s
vf ≈ 6.68 m/s
The ball hits the ground with a speed of about 6.68 meters per second.
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We assume the launch direction is either up or down.
