Answer:
Explanation:
Let the tension in the string be T . At the top of the circle , total force acting on them = T + mg . This will provide centripetal force
T + mg = m v² / r
4 + .25 x 9.8 = .25 x v² / .62
6.45 = .25 v² / .62
v² = 16
v = 4 m /s .
When you talk about rate, you will expect that it will be in terms of a time unit. It measures how fast it is going. So, you would expect that the denominator is in time units. For the movement, you can measure this with either distance or velocity.
So, for the first variety, you would need distance and time to measure the rate of how far you go at a certain time. It is also called as velocity. For the second variety, you would need velocity and time to measure the rate of how fast you are going at a certain interval. It is also called as acceleration.
Answer:
Explanation:
Answer:
Explanation:
The half life is the time taken for half of a radioactive substance to disintegrate.
The shorter the half life, the larger the decay constant and the faster the decay process.
For a very large half life, it would take a very long time for the radioactive nuclide to decay to half.
With each half life reached, a new set of daughter cell is formed. Atoms that have short half life would decay rapidly. Every radionuclide has its own characteristic half-life.
If the number of half-lives increases, then the number of radioactive atoms decreases, because approximately half of the atoms' nuclei decay with each half-life. With this observation, we can hypothesise and conduct experiment to support the assertion that as the number of half-lives increases then the number of radioactive atoms decreases.
cardiac muscle is striated. Uniquely, the cells of this kind of muscle are joined strongly together at adherens junctions that “enable the heart to contract forcefully without ripping the fibers apart.”
Answer:
It has potential energy
PE = 15450.75 J
Explanation:
we know its potential energy because the carriage is not moving, although it can
PE = mgh
in this case, m is 75, h is 21, and g is always 9.81
plug these in: PE = (75) (21) (9.81)
your answer: PE = 15450.75 J
