Answer:
(D) is correct option.
Explanation:
At a particular time, the potential energy of a rock is 500 J and its kinetic energy is 600 J.
It is required to find the mechanical energy of the rock. Mechanical or total energy is the sum of kinetic and potential energy. So,
TE = K+ P
TE = 500 J + 600 J
TE = 1100 J
So, the total mechanical energy of a rock is 1100 J. Hence, the correct option is (D).
Draw an x y axis
3 miles west is 3 miles to the left, -3
4 miles south is 4 miles down, -4
connect the the point to the origin, that side is what you are looking for
that side is also hypotenus
using Pythagorean theorem
sqrt(-4^2 + 3^2)
sqrt(25)
5
your displacement is 5
Answer:
(C) At a recently discovered site once used as an observatory by the Anasazi, ancient pueblo dwellers of New Mexico, patterns of light and shadow were employed to establish the precise limits of the positions of the Sun and Moon over a nineteen-year cycle.
Explanation:
Option D does not convey the information that the site was once used as an observatory
Option E alters the meaning of the sentence. The two phrases, "....at a recently discovered place" and "....once used the site as an observatory", used together in this sentence bring about an unnecessary redundancy that change the meaning of the sentence.
The adjective "Where" is used to refer to the Anasazi, a population of humans. This is wrong.
Only option C clearly and correctly conveys the true meaning of the sentence.
<span>Pollination is the process by which pollen is transferred to the female part of a plant. The stigma is the central part of the flower, that is supported by a style and is part of the female reproductive organ within plants. Its structure is optimised to promote pollination by having hairs, sticky surfaces and three-dimensional sculptures that capture and trap pollen.</span>
Answer is D.
Speed:
Use relative speed to simplify the situation. Since the trains are moving in opposite directions, you can add the speeds and pretend the first train is stationary (moving at 0m/s) and the second train is moving at 50m/s.
Distance:
The front of the second train needs to travel 120m to get from the front to the back of the first train. When the front of the second train is at the back of the first train, the back of the second train is still 10m in front of the first train. The back therefore has to travel 130m to clear the first train. The total distance over which the trains are overlapping in this scenario is therefore 120 + 130 = 250m.
You have speed and you have distance so now just calculate time:
v = d / t
50 = 250 / t
t = 5s
