Comets<span> are small, irregularly shaped bodies in the solar system composed mainly of ice and dust that typically measure a few kilometers across. They travel around the sun in very elliptical orbits that bring them very close to the Sun, and then send them out past Neptune. There are two categories of comet, based on the amount of time they take to orbit the Sun. Short-period comets take less than 200 years, and long-period comets take over 200 years, with some taking 100,000 to 1 million years to orbit the Sun. The short-period comets are found near the ecliptic, which means they are orbiting the Sun in same plane as the planets. The short-period comets are thought to originate in the Kuiper Belt, an area outside Neptune's orbit (from about 30 to 50 AU) that has many icy comet-like objects. The long-period comets tend to have orbits that are randomly oriented, and not necessarily anywhere near the ecliptic. They are thought to originate in the Oort cloud. The Oort cloud has never been observed, but is believed to have at least 10</span>12<span>icy objects located between 3000 AU and 100,000 AU in a spherical distribution around the Sun.</span>
Given:
Object in circular motion 25 m/s
1 second to go quarter circle
Required:
Centripetal acceleration:
Solution:
Acceleration = v2/r
Where v is the velocity and r is
the radian
Substituting the values into the
equation,
Acceleration = v2/r = (25
m/s)2/(4*pi/180) = 8952.47 m2/s2
Answer: option (D)
Explanation:
The potential energy of each of the students is given below as
P.E(student A) = mgh, where m = mass of student A, g is acceleration due to gravity and h = height of the high dive structure.
The mass of student B is twice as much as that of A, hence his mass is 2m and his potential energy is given below as
P.E ( student B) =2mgh = 2(mgh)
Recall that the relationship between potential energy and work done is that
Work done = - (change in potential)
For student A, work done = - mgh
For student B, work done = - 2mgh
From the equations above it can be seen that student B will do twice the work in getting to the high dive structure than student A hence validating option D.
