Answer:
Weight of the fluid that the object displaces.
Explanation:
When the fluid is completely immersed in a fluid, it experiences pressure from all the direction. While the object is immersed in the fluid a force acts on it in the opposite direction, i.e., upwards. This force is termed as buoyant force.
Also, as per the Archimedes' Principle, the force experience by the object is the same as the weight of the fluid that gets displaced by the object.
Thus on complete immersion of the object in the fluid, it experiences the force same as the weight of the fluid that gets displaced
Answer:
The lethal voltage for the electrician under those conditions is 126.5 V.
Explanation:
To discover what is the lethal voltage to the electrician we need to find out what is the voltage that produces 55 mA = 0.055 A when across a resistance of 2300 Ohms (Electrician's body resistancy). For that we'll use Ohm's Law wich is expressed by the following equation:
V = i*R
Where V is the voltage we want to find out, i is the current wich is lethal to the electrician and R is his body resistance. By applying the given values we have:
V = 0.055*2300 = 126.5 V.
The lethal voltage for the electrician under those conditions is 126.5 V.
Answer:
e) 120m/s
Explanation:
When the ball reaches its highest point, its velocity becomes zero, meaning
.
where
is the initial velocity.
Solving for
we get
which is the time it takes the ball to reach the highest point.
Now, after the ball has reached its highest point, it turns around and falls downwards. After time
since it had reached the highest point, the ball has traveled downwards and the velocity
it has gained is
,
and we are told that this is twice the initial velocity
; therefore,

which gives

Thus, the total time taken to reach velocity
is


This
, we are told, is 36 seconds; therefore,

and solving for
we get:



which from the options given is choice e.
Answer:
0.25m/s
Explanation:
Given parameters
m₁ = 5kg
v₁ = 1.0m/s
m₂ = 15kg
v₂ = 0m/s
Unknown:
velocity after collision = ?
Solution:
Momentum before collision and after collision will be the same. For inelastic collision;
m₁v₁ + m₂v₂ = v(m₁ + m₂)
Insert parameters and solve for v;
5 x 1 + 15 x 0 = v (5 + 15 )
5 = 20v
v =
= 0.25m/s