Explanation:
A lever is a rigid bar which moves freely about a fixed point called fulcrum....
The types of lever are :
- First class lever
- Second class lever
- Third class lever....
Answer: the minimum spacing that must be there between two objects on the earth's surface if they are to be resolved as distinct objects by this telescope 6.45 cm
Explanation:
Given that;
diameter of the mirror d = 1.7 m
height h = 180 km = 180 × 10³ m
wavelength λ = 500 nm = 5 × 10⁻⁹ m
Now Angular separation from the peak of the central maximum is expressed as;
sin∅= 1.22 λ / d
sin∅ = (1.22 × 5 × 10⁻⁹) / 1.7
sin∅ = 3.588 × 10⁻⁷
we know that;
sin∅ = object separation / distance from telescope
object separation =
sin∅ × distance from telescope
object separation = 3.588 × 10⁻⁷ × 180 × 10³
object separation =6.45 × 10⁻² m
then we convert to centimeter
object separation = 6.45 cm
Therefore the minimum spacing that must be there between two objects on the earth's surface if they are to be resolved as distinct objects by this telescope 6.45 cm
Answer:
The initial velocity was 9.39 m/s
Explanation:
<em>Lets explain how to solve the problem</em>
The ball is thrown straight upward with initial velocity u
The ball reaches a maximum height of 4.5 m
At the maximum height velocity v = 0
The acceleration of gravity is -9.8 m/s²
We need to find the initial velocity
The best rule to find the initial velocity is <em>v² = u² + 2ah</em>, where v is
the final velocity, u is the initial velocity, a is the acceleration of
gravity and h is the height
⇒ v = 0 , h = 4.5 m , a = -9.8 m/s²
⇒ 0 = u² + 2(-9.8)(4.5)
⇒ 0 = u² - 88.2
Add 88.2 to both sides
⇒ 88.2 = u²
Take square root for both sides
⇒ u = 9.39 m/s
<em>The initial velocity was 9.39 m/s</em>
Answer:
D
Explanation:
P=Work/Time
The rate at which work is done matches that.
There's no such thing as "an unbalanced force".
If all of the forces acting on an object all add up to zero, then we say that
<span>the group </span>of forces is balanced. When that happens, the group of forces
has the same effect on the object as if there were no forces on it at all.
An example:
Two people with exactly equal strength are having a tug-of-war. They pull
with equal force in opposite directions. Each person is sweating and straining,
grunting and groaning, and exerting tremendous force. But their forces add up
to zero, and the rope goes nowhere. The <u>group</u> of forces on the rope is balanced.
On the other hand, if one of the offensive linemen is pulling on one end of
the rope, and one of the cheerleaders is pulling on the other end, then their
forces don't add up to zero, because even though they're opposite, they're
not equal. The <u>group</u> of forces is <u>unbalanced</u>, and the rope moves.
A group of forces is either balanced or unbalanced. A single force isn't.
