Answer:
, assuming that the gravitational field strength is 
.
Explanation:
Notice that both the speed and the direction of motion of this block are constant. In other words, the velocity of this block is constant.
By Newton's Second Law, the net force on this block would be 
. External forces on this block should be balanced. Thus, the magnitude of the (downward) weight of this block should be equal to the magnitude of the (upward) force that the boy applies on this block.
Let 
denote the mass of this block. It is given that 
. The weight of this block would be:
.
Hence, the force that the boy applies on this block would be upward with a magnitude of 
.
The mechanical work that a force did is equal to the product of:
- the magnitude of the force, and
- the displacement of the object in the direction of the force.
The displacement of this block (upward by 
) is in the same direction as the (upward) force that this boy had applied. Thus, the work that this boy had done would be the product of:
- the magnitude of the force that this boy exerted, , and
- the displacement of this block in the direction, .
.
Answer:
The Hydrostatic force is 
The location of pressure center is 
Explanation:
From the question we are told that
The height of the gate is 
The weight of the gate is 
The height of the water is 
The density of water is 
Note used 
for height of water and height of gate immersed by water since both have the same value
The area of the gate immersed in water is mathematically represented as
substituting values
The hydrostatic force is mathematically represented as
Where
So
The center of pressure is mathematically represented as
Where 
is the moment of inertia of the gate which mathematically represented as
The is the height of gate immersed in water
Thus
Answer:
9.877 m/s^2
Explanation:
The acceleration can be computed from ...
d = (1/2)at^2
(1600 m) = (1/2)a(18 s)^2
a = (1600/162) m/s^2 ≈ 9.877 m/s^2
Answer: Option (b) is the correct answer.
Explanation:
The force of gravity acting on an object helps in determining the weight of an object. But a place where there will be no gravity or have zero gravitational pull then it means the person will be weightless.
For example, force of gravity on moon is zero which means any object or person on moon will be weightless.
On the other hand, when a child is in the air as she plays on a trampoline then it means gravitational pull form the earth is acting on it. So, it will definitely has some weight.
Similarly, a scuba diver exploring a deep-sea wreck is under the ground where there will be force of gravity. Hence, it will also have some weight.
Thus, we can conclude that an astronaut on the Moon is the person who is weightless.
