Threshhold frequency is defined as the minimum light frequency necessary to start photo-electric emission from the surface. This frequency is just effecient enough to emit electrons without any additional force or energy. this minimum frequency creates the necessary result that is sought by the person. The photo electric emission for certain metals can occir with threshhold frequency. The importance of this threshhold frequency lies in the fact that this has been used to create numerous instruments like amplifiers for use of people.
The acceleration of gravity is
9.8 m/s^2 down.
When an object falls out of a hand, its speed after 1.8s is
(9.8)x(1.8) = 17.6 m/s down.
It doesn't matter what it is, how much it weighs, or how high it was dropped from.
If it's more than 17.6 m/s, then this happened on a different, bigger planet.
If it's less than 17.6 m/s, then it must have hit something on the way down, like some air or something.
If the 30 N on the rope were pulled straight up, it would offset the force of gravity ( m g = 10 kg * 9.8 N/kg = 98 N) , leaving a net force up from the ground on the sled of 98-30 = 68 N. Since the rope is pulled at the angle of 25o, only part of the force is in the upward direction, (30N)(sin(25) = (30)(.423) = 12.7. So the net force becomes 98 N down offset by 12.7 up or 98-12.7 = 85.3 N. Ah, there it is: C.
At the time of quark confinement, when the universe was 10-6 seconds old, there is found to be one additional proton for every billion antiprotons.
<h3>What is quark confinement?</h3>
Note that one quark is never found on its own but if particles are said to be smashed together and quarks are found, they are said to be like ends of rubber bands that expands.
Hence, At the time of quark confinement, when the universe was 10-6 seconds old, there is found to be one additional proton for every billion antiprotons.
Learn more about quark from
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