Answer:
6.32m/s
Explanation:
note:Now these calculations are based in the fact that acc. due to gravity is 10m/s²
okay so I'm thinking you think the speed of a body depends on the mass of the body also,umh... well it doesn't at all!
when two bodies of different masses fall from the same height,they fall at the same time( this is just to say)
now enough of the talking let solve....
so the ball was dropped .ie from rest to the ground through a distance of 2m,
the formula for calculating the distance if a body moving in a straight line is given by:
S=ut + ½at² where u is initial velocity, a is acceleration ( of the body or due to gravity, but since its falling freely under the influence of gravity its " we use the acceleration due to gravity ,which is 10m/s²) and t is the time taken to cover the distance.
from our question the ball was dropped from rest thus its u is 0 therefore we use this equation to find the time it took to touch ground (S=½at²)
solving ....
we get t to be 0.632s
to find the speed we substitute t in the equation below:
V=u+at ,but since u=0
V=at =10•0.632=6.32m/s
therefore the speed the body uses to strike the ground is 6.32m/s
Answer:
C
Explanation:
First find the electrical wattage
W = I^2 * R
R = 12 ohms
I = 2 amps
Wattage = 2^2 * 12
Wattage = 4* 12
Wattage = 48 watts.
Now you need to use the power formula
Work = Power * Time
Work = ?
Power = 48 watts
Time = 3 minutes = 3 * 60 = 180 seconds.
Work = 48 * 180
Work = 8640 J
That's C
<u>Answer</u>
3.7 Km south
<u>Explanation</u>
The definition of displacement is the distance traveled in a specific direction. It is the vector quantity. We add displacements like the way we add vectors.
Taking the direction towards North to be positive (+1.7 Km), the distance towards south would be negative (-5.4 Km).
Now lets add the two values.
(+1.7) + (-5.4) = 1.7 - 5.4
= - 3.7 Km But negative was towards south.
∴ Answer = 3.7 Km south.
Answer: v = 2.24 m/s
Explanation: The <u>Law</u> <u>of</u> <u>Conservation</u> <u>of</u> <u>Energy</u> states that total energy is constant in any process and, it cannot be created nor destroyed, only transformed.
So, in the toy launcher, the energy of the compressed spring, called <u>Elastic</u> <u>Potential</u> <u>Energy (PE)</u>, transforms into the movement of the plastic sphere, called <u>Kinetic</u> <u>Energy (KE)</u>. Since total energy must be constant:
where the terms with subscript i are related to the initial of the process and the terms with subscript f relates to the final process.
The equation is calculated as:
v = 2.24
The maximum speed the plastic sphere will be launched is 2.24 m/s.
Answer:
- The work made by the gas is 7475.69 joules
- The heat absorbed is 7475.69 joules
Explanation:
<h3>
Work</h3>
We know that the differential work made by the gas its defined as:
We can solve this by integration:
but, first, we need to find the dependence of Pressure with Volume. For this, we can use the ideal gas law
This give us
As n, R and T are constants
But the volume is:
Now, lets use the value from the problem.
The temperature its:
The ideal gas constant:
So:
<h3>Heat</h3>
We know that, for an ideal gas, the energy is:
where its the internal energy of the gas. As the temperature its constant, we know that the gas must have the energy is constant.
By the first law of thermodynamics, we know
where is the Work made by the gas (please, be careful with this sign convention, its not always the same.)
So: