Answer:
1) The final displacement of cyclist is 20.8 km.
2) The average velocity of cyclist is 18.35 m/h
Explanation:
The path traced by the cyclist is as shown in the attached figure
from the attached figure we can see
1) Initial distance covered = 8.0 km east therefore OA = 8.0 km
2) When the cyclist turns and travels 3.2 km west thus AB = 3.2 km
3) From B the cyclist turns and travels 16 km east thus BC = 16.0 km
As we can see that the total displacement is OC = OA- AB + BC = 8.0-3.2+16 = 20.8 km
Thus the final displacement is 20.8 km.
Part b)
By definition of average velocity we have
![v_{avg}=\frac{Total\cdot Displacement}{Total\cdot Time}=\frac{20.8}{20+8+40}=0.305km/min=18.35km/hr](https://tex.z-dn.net/?f=v_%7Bavg%7D%3D%5Cfrac%7BTotal%5Ccdot%20Displacement%7D%7BTotal%5Ccdot%20Time%7D%3D%5Cfrac%7B20.8%7D%7B20%2B8%2B40%7D%3D0.305km%2Fmin%3D18.35km%2Fhr)
I would choose the vinegar before baking soda because the baking soda is what is making the chemical reaction with the vinegar. Both need eachother but the vinegar is a less powerful reactant than the baking soda.
The correct matches are as follows:
<span>1. Mechanical Energy
</span>This is the energy of motion and position - Kinetic Energy and Potential Energy are included here.
<span>
2. Electrical Energy
</span>This is the type of energy that is given off as a result of electrons (charges!) moving through a conductor.
<span>
3. Light Energy
</span>This is the only form of energy we can see with our eyes!
<span>
4. Thermal Energy
</span>This is heat energy! It can be transferred through conduction, convection, or radiation.
<span>
5. Sound Energy
</span>This is energy that is transmitted through vibrations.
<span>
6. Kinetic Energy
</span>This is the energy that all moving objects have. <span>
7. Potential Energy
</span>This is stored energy, waiting to be used!
Answer:
<em>P = 1500 Watt</em>
Explanation:
<u>Mechanical Work and Power
</u>
Mechanical work is the amount of energy transferred by a force.
Being F the magnitude of the force vector and s the distance, the work is calculated as:
W=F.s
Power is the amount of energy transferred or converted per unit of time. In the SI, the unit of power is the watt, equal to one joule per second.
The power can be calculated as:
![\displaystyle P=\frac {W}{t}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20P%3D%5Cfrac%20%7BW%7D%7Bt%7D)
Where W is the work and t is the time.
The force to be considered is the weight of the mass of m=100 kg,
:
F = 100 * 10 = 1000 N
The distance is s=3 m, thus the work done by the weight lifter is:
W = 1000 N * 3 m
W = 3000 J
Finally, the power is:
![\displaystyle P=\frac {3000}{2}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20P%3D%5Cfrac%20%7B3000%7D%7B2%7D)
P = 1500 Watt
Answer:
9 and 3 N
Explanation:
Forces in the same direction sum up to produce the resultant force;
One force subtract the other will give the resultant force when they are in opposite directions;
Lets say one direction is forwards and the opposite backwards;
We have one force, let's say force A, in the forwards direction and another force, force B, acting in the same (forwards) or opposite (backwards) direction;
If B is acting in the same direction, then the resultant force (in this case) will be as follows:
A + B = 12
If B is acting in the opposite direction, then the resultant force will be as follows:
A - B = 6
Summing the two equations will allow us to solve for A:
A + B + (A - B) = 12 + 6
2A = 18
A = 9
Substitute this into either of the above equations and we can solve for B:
(9) - B = 6
B = 9 - 6
B = 3