Answer:
C) 4 seconds
Explanation:
The height of an object is given by the following formula:
To find the flight time you equal the height s to zero:
Then, you have a quadratic equation of the form:
you use the quadratic formula in order to find the roots of the polynomial:
you take the positive value of t because this has physical meaning.
Hence:
the time is C) 4 seconds
Answer:
The rate of change of the height is - 4 ft/s
Solution:
As per the question:
Height of the person, y = 5 ft
The rate at which the person walks away,
Distance of the spotlight from the wall, x = 40 ft
Now,
To calculate the rate of change in the height, of the person when, x = 10 m:
From fig 1.
xy = 200 (1)
Differentiating the above eqn w.r.t time t:
Thus
(2)
From eqn (1):
When x = 10 ft
10y = 200
y = 20 ft
Using eqn (2):
The wall will push back with an equal and opposite force, as defined by Newton's Third Law, so the wall will exert -200 N of force
Comets are divided into two types. Long-period comets are the comets that take more than two hundred years to finish an orbit throughout the Sun originate from the Oort Cloud.
<u>Explanation:</u>
- The Oort Cloud has sufficient distance apart of the Sun than the Kuiper Belt, it seems that the Oort Cloud objects were made closer to the Sun than the Kuiper Belt things.
- Long-period comets have highly eccentric orbits.
- The Oort cloud is considered to own a large range commencing from among 2,000 and 5,000 AU to 50,000 AU.
- The chemical makeup of long-period and short-period comets is quite alike.