Answer:
KE = m
Explanation:
In the generation of energy from hydroelectric power station, the motion of water, and the turbines are paramount. The falling flowing water turns the blades of the turbine, which in-turn causes the movement of a coil within a strong magnetic field.
The motion of the coil which cuts the strong magnetic field induces current. Thus, the system generates electrical energy.
The equation that links kinetic energy (KE), mass (m) and speed (v) can be expressed as:
KE = m
Answer:
v₃ = 3.33 [m/s]
Explanation:
This problem can be easily solved using the principle of linear momentum conservation. Which tells us that momentum is preserved before and after the collision.
In this way, we can propose the following equation in which everything that happens before the collision will be located to the left of the equal sign and on the right the moment after the collision.
where:
m₁ = mass of the car = 1000 [kg]
v₁ = velocity of the car = 10 [m/s]
m₂ = mass of the truck = 2000 [kg]
v₂ = velocity of the truck = 0 (stationary)
v₃ = velocity of the two vehicles after the collision [m/s].
Now replacing:
Answer: n=4
Explanation:
We have the following expression for the volume flow rate of a hypodermic needle:
(1)
Where the dimensions of each one is:
Volume flow rate
Radius of the needle
Length of the needle
Pressures at opposite ends of the needle and
Viscosity of the liquid
We need to find the value of whicha has no dimensions, and in order to do this, we have to rewritte (1) with its dimensions:
(2)
We need the right side of the equation to be equal to the left side of the equation (in dimensions):
(3)
(4)
As we can see must be 4 if we want the exponent to be 3:
(5)
Finally:
(6)
Answer:
Solving for time :
(There are 4 formulas from linear motion. These formulas are very helpful as it allows us to prevent complicated calculations. Choose among the four that has : 1. The most constants known
2. The unknown constant that we want to solve)
s = (1/2)(u+v)t <--- one of the formulas
from linear motion
s (distance) = 0.05m
u (initial velocity) = 100m/s
v (final velocity) = 0 m/s (it stops)
t (time taken for change in velocity) = to be found
0.05 = (1/2)(100+0)t
t = 0.001 seconds
Solving for the resistant force :
Since the bullet hits the bag with an impulsive force and stops, the force that stops the bullet is the resistant force.
When the bullet stops :
F net = 0
F r = F imp
F r = (mu -mv)/t
F r = (0.01x100-0.01x0)/0.001
F r = 1/0.001
F r = 1000N