Answer:
They are inversely proportional with each other. ∝
Explanation:
By the equation V=IR, assume V is constant.
Since I and R are on the same side,
if I increase, R decreases, or the vice versa.
Answer: 6,400 km
Explanation:
The weight of a person is given by:
where m is the mass of the person and g is the acceleration due to gravity. While the mass does not depend on the height above the surface, the value of g does, following the formula:
where
G is the gravitational constant
M is the Earth's mass
r is the distance of the person from the Earth's center
The problem says that the person weighs 800 N at the Earth's surface, so when r=R (Earth's radius):
(1)
Now we want to find the height h above the surface at which the weight of the man is 200 N:
(2)
If we divide eq.(1) by eq.(2), we get
By solving the equation, we find:
which has two solutions:
--> negative solution, we can ignore it
--> this is our solution
Since the Earth's radius is , the person should be at above Earth's surface.
We use the law of Cosines, resultant force
Here, and are forces acting at angle with each other.
Given , and .
Substituting these given values in above formula we get
.
Thus, the resultant force is 156 N.
Option (C) is correct.
A projectile is an object launched at an angle with the horizontal and allowed to move freely under the effect of gravity alone.
Thus the only external force acting on a projectile is the force of gravity.There may be the force of air friction acting but for all practical purposes, we neglect its effect.
Thus only force of gravity acts during projectile motion.
Hello
1) The total vertical acceleration of the rocket is
, where
and
is the gravitational acceleration that points downward.
2) This is an accelerated motion, so we can write the law of motion as
where S is the total distance covered by the rocket after time t. We can then substitute
into the previous equation and we get
And so, after
s, we get
m, which is the height reached by the rocket after 10 seconds.