Answer:
2.96 cm
Explanation:
By Hook's law
Force(F) = Spring constant(k) × Extension(d)
F = k × d
Force is the weight of the object, F = W = mg
So we get, mg = kd ⇒ m ∝ d
2.5 ∝ 1.68 --------------(1)
4.4 ∝ d' --------------(2)
From (1) & (2), 4.4/2.5 = d'/1.68
d' = 2.96 cm ⇒ the required extension.
Answer:
0.71 m/s
Explanation:
We find the time it takes the stone to hit the water.
Using y = ut - 1/2gt² where y = height of bridge, u = initial speed of stone = 0 m/s, g = acceleration due to gravity = -9.8 m/s² (negative since it is directed downwards)and t = time it takes the stone to hit the water surface.
So, substituting the values of the variables into the equation, we have
y = ut - 1/2gt²
82.2 m = (0m/s)t - 1/2( -9.8 m/s²)t²
82.2 m = 0 + (4.9 m/s²)t²
82.2 m = (4.9 m/s²)t²
t² = 82.2 m/4.9 m/s²
t² = 16.78 s²
t = √16.78 s²
t = 4.1 s
This is also the time it takes the raft to move from 5.04 m before the bridge to 2.13 m before the bridge. So, the distance moved by the raft in time t = 4.1 s is 5.04 m - 2.13 m = 2.91 m.
Since speed = distance/time, the raft's speed v = 2.91 m/4.1 s = 0.71 m/s
Answer:
the energy emission process is due to nuclear fusion
Explanation:
In the planetary system the energy emitted by bodies is a part of the energy received by a hot body (star), this star is what creates the entire energy cycle of a given planet. This creates the entire tidal movement, continental drift
If the planets reach a certain size the gravitational force near their center is so great that the atoms are crushed and some beginnings of fusion processes are formed where some atoms are transformed from hydrogen to helium releasing a certain amount of energy and heat that believe that the planet emits more energy than it receives from its star.
In summary, the energy emission process is due to nuclear fusion
Answer:
The correct option is (c) "it bounces the light towards a focal point"
Explanation:
There are two types of spherical mirrors i.e. concave and convex.
A concave mirror is a type of spherical mirror that is curved inwards. For this type of mirror the rays of light are bounced back and converge to the focal point of the mirror.
So, the correct option is (c).
Answer:
1.11 s.
Explanation:
From the question given above, the following data were obtained:
Height (H) = 6 m
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) =.?
The time taken for the branch to hit the ground can be obtained as follow:
H = ½gt²
6 = ½ × 9.8 × t²
6 = 4.9 × t²
Divide both side by 4.9
t² = 6/4.9
Take the square root of both side
t = √(6/4.9)
t = 1.11 s
Therefore, it will take 1.11 s for the branch to hit the ground.
