The easiest, non-technical way to think about it is like this:
-- A scalar is a quantity that has a size but no direction.
Those include temperature, speed, cost, volume, distance, etc.
One number is all there is to know about it, and there's no way you can
add more of the same stuff to it that would cancel both of them out.
-- A vector is a quantity that has a size and also has a direction.
Those include force, displacement, velocity, acceleration, etc.
It takes more than one number to completely describe one of these.
Also, if you combine two of the same vector quantity in different ways,
you can get different results, and they can even cancel each other out.
Here are some examples. Notice that in each of these examples,
every speed has a direction that goes along with it. This turns the
scalar speed into a vector velocity.
If you're walking inside a bus, and the bus is driving along the road,
then your velocity along the road is the sum of your walking velocity
inside the bus plus the velocity of the bus along the road.
-- If you're walking north up the middle of the bus at 2 miles per hour
and the bus is driving north along the road at 20 miles per hour, then
your velocity along the road is 22 miles per hour north.
-- If you're walking south towards the back of the bus at 2 miles per hour
and the bus is driving north along the road at 5 miles per hour, then your
velocity along the road is 3 miles per hour north.
-- If you're walking south towards the back of the bus at 2 miles per hour
and the bus is just barely rolling north along the road at 2 miles per hour,
then your velocity along the road is zero.
-- If you're in a big railroad flat-car that's rolling north along the track
at 2 miles per hour, and you walk across the flat-car towards the east
at 2 miles per hour, then your velocity along the ground is 2.818 miles
per hour toward the northeast.
Answer:
107 m
Explanation:
Convert km/h to m/s:
128.4 km/h × (1000 m / km) × (1 h / 3600 s) = 35.67 m/s
Distance = rate × time
d = 35.67 m/s × 3.0 s
d = 107 m
Answer:
B) 2.7 g of aluminium has a volume of 1 cm^3
Explanation:
Density can be defined as mass all over the volume of an object.
Simply stated, density is mass per unit volume of an object.
Mathematically, density is given by the equation;
If the density of aluminum is 2.7 g/cm³, it simply means that 2.7 g of aluminium has a volume of 1 cm³
Check:
Given the following data;
Mass = 2.7 grams
Volume = 1 cm³
Substituting into the formula, we have;
Density = 2.7 g/cm³
<h3><u>Answer;</u></h3>
C. 12 units
<h3><u>Explanation;</u></h3>
- If the strength of the magnetic field at B is 3 units, the strength of the magnetic field at A is 12 units
- Magnetic field strength is one of two ways that the intensity of a magnetic field can be expressed.
- <em><u>The strength of the field is inversely proportional to the square of the distance from the source. This means that If the distance between two points in magnetic filed is doubled the magnetic force between them will fall to a quarter of the initial value. </u></em>
- <em><u>On the other hand, if the distance between two magnets is halved the magnetic force between them will increase to four times the initial value.</u></em>
Answer:
a) the magnitude of r is 184.62
b) the direction is 37.74° south of the negative x-axis
Explanation:
Given the data in the question;
as illustrated in the image blow;
To find the the magnitude of r, we will use the Pythagoras theorem
r² = y² + x²
r = √( y² + x²)
we substitute
r = √((-113)² + (-146)²)
r = √(12769 + 21316 )
r = √(34085 )
r = 184.62
Therefore, the magnitude of r is 184.62
To find its direction, we need to find ∅
from SOH CAH TOA
tan = opposite / adjacent
tan∅ = -113 / -146
tan∅ = 0.77397
∅ = tan⁻¹( 0.77397 )
∅ = 37.74°
Therefore, the direction is 37.74° south of the negative x-axis
