Velocity:
Velocity is change in displacement with respect to time:
Analysing the units, meters (displacement) and seconds (time) are basic units:
Therefore the unit of velocity is m/s
Force:
Newton's second law of motion:
Kilogram (mass) is a basic unit, and accelerations unit can be found using the equation:
Analysing the units:
Therefore, the unit of force is:
Pressure:
Pressure is given by the equation:
where S is area of effect, F is force
Area for a basic rectangle (geometric shape is arbitrary for dimensional analysis) is found by multiplying two lengths:
![[l^2]=m^2](https://tex.z-dn.net/?f=%5Bl%5E2%5D%3Dm%5E2)
, the unit of area
Dividing the aforementioned unit of force by the unit of area:
, the unit of pressure
Work:
Work is given by the equation:
, (dot product may be assumed as normal multiplication for the purposes of unit analysis)
Knowing displacement's (x) unit is m:
![[W]=\frac{kgm}{s^2}m=\frac{kgm^2}{s^2}](https://tex.z-dn.net/?f=%5BW%5D%3D%5Cfrac%7Bkgm%7D%7Bs%5E2%7Dm%3D%5Cfrac%7Bkgm%5E2%7D%7Bs%5E2%7D)
, the unit of work.
Answer:
Explanation:
The cross product of two vectors is given by
Where, θ be the angle between the two vectors and \widehat{n} be the unit vector along the direction of cross product of two vectors.
Here, K x i = - j
As K is the unit vector along Z axis, i is the unit vector along X axis and j be the unit vector along axis.
The direction of cross product of two vectors is given by the right hand palm rule.
So, k x i = j
j x i = - k
- j x k = - i
i x i = 0
Answer:
Explanation:
Assuming no energy lost, according to the law of conservation of energy, the kinetic energy of the automobile becomes potential energy after the crash:
Here m is the automobile's mass, v is the speed of the car before impact, k is the "bumper" constant and x is the compression of the bumper due to the collision. Solving for v:
Answer:
C. Fill two identical pots with equal volumes of salt water and tap water and use a stopwatch to determine the time it takes each pot to boil.
Explanation:
<u>A) is incorrect</u> because Peter should have the same testing environment for both of his experiments.
He should choose the same method of boiling the salt water and tap water because the stovetop and the microwave could also affect the results and make them unreliable.
<u>B) is incorrect</u> because Peter should not estimate the time it takes the salt water and tap water to boil.
Peter should measure and record the amount of time that it takes these substances to boil in order to have an accurate, valid experimental thesis.
<u>C) is correct</u> because Peter uses the same volume of salt water and tap water, fills them into two identical pots, and uses a stopwatch to determine the amount of time it takes each pot to boil.
The stopwatch makes the experiment more valid and accurate compared to the previous methods, and the identical pots and amounts of water help this experiment become even more precise.
<u>D) is incorrect</u> because the variables in the experiment are not controlled amounts and will therefore produce an inaccurate and invalid experiment.
Answer:
a) false
b) True
c) True
d) False
e) False
Explanation:
a) False
For a diverging lens, the focal length is negative while it is positive for a converging lens
b) True
Image distances for virtual images are always negative and it also forms on the the same side of the lens as the object and is enlarged
c) True
d) False
For a diverging lens, the focal length is negative while it is positive for a converging lens
e) False
Image distances for virtual images are always negative and it also forms on the the same side of the lens as the object and is enlarged
