The correct answer is the last one:
A and C are different elements, while D is an isotope of C.
In fact, A and C are different elements, because they have a different number of protons in the nucleus (A has 3 protons, while C has 4 protons). Instead, D and C are the same element (they both have 4 protons in the nucleus), but they are different isotopes since they have a different number of neutrons (D has 4 neutrons while C has 3 neutrons)
Answer: D. 5cm
Explanation:
Given the following :
Focal length (f) = - 6.0 cm
Height of object = 15.0cm
Distance of object from mirror (u) = 12.0cm
Height of image produced by the mirror =?
Firstly, we calculate the distance of the image from the mirror.
Using the mirror formula
1/f = 1/u + 1/v
1/v = 1/f - 1/u
1/v = 1/-6 - 1/12
1/v = - 1/6 - 1/12
1/v = (- 2 - 1) / 12
1/v = - 3 / 12
v = 12 / - 3
v = - 4
Using the relation :
(Image height / object height) = (- image distance / object distance)
Image height / 15 = - (-4) / 12
Image height / 15 = 4 / 12
Image height = (15 × 4) / 12
Image height = 60 / 12
Image height = 5cm
I did it last year. I thinks its A
Answer:
Explanation:
When the two or more forces acting on a body such tat the net force on the body or the acceleration of the body is zero, then such forces are balanced forces.
For example, in the game of tug of war, both the teams pulls the rope with same force but in opposite directions so that the net acceleration is zero it means a balanced force is acting on the rope.
When tow or more forces acting on a body and there is some net force or acceleration of the body, then the forces are said to be unbalanced.
For example, if we push a box along the plane, the net force is non zero and the forces are unbalanced.
Answer:
All the planets have nearly circular orbit except the Pluto
Explanation:
Planets closer to the Sun move around their orbits at a very high speed than planets farther from the Sun.
All the planets except Pluto, orbit the Sun in nearly the same plane.
All the planets have nearly circular orbits except Pluto because of it's distance from the sun which is over 5,000,000,000km
