Answer:
A quantity that does not depend on the direction is called a scalar quantity. Vector quantities have two characteristics, a magnitude, and a direction. Scalar quantities have only a magnitude. When comparing two vector quantities of the same type, you have to compare both the magnitude and the direction.
Scalar quantities only have magnitude (size). Scalar quantities include distance...
A quantity that is specified by both size and direction is a vector. Displacement includes both size and direction and is an example of a vector. However, distance is a physical quantity that does not include a direction and isn't a vector.
Explanation:
hope this helps...
As per the question Bob drops the bag full with feathers from the top of the building.
The mass of the bag(m)= 1.0 lb
Let the air resistance is neglected.As the bag is under free fall ,hence the only force that acts on the bag is the force of gravity which is in vertical downward direction.
Here the acceleration produced on bag due to the free fall will be nothing else except the acceleration due to gravity i.e g =9.8 m/s^2
Here we are asked to calculate the distance travelled by the bag at the instant 1.5 s
Hence time t= 1.5 s
From equation of kinematics we know that -
S=ut + 0.5at^2 [ here S is the distance travelled]
For motion under free fall initial velocity (u)=0.
Hence S= 0×1.5+{0.5×(-9.8)×(1.5)^2}
⇒ -S =0-11.025 m
⇒ S= 11.025 m
=11 m
Here the negative sign is taken only due to the vertical downward motion of the body .we may take is positive depending on our frame of reference .
Hence the correct option is B.
Answer:
Radiation
Explanation:
The sun radiates energy to the earth to make it warmer near the equator.
Answer:
d) The 2 athletes reach the same height, because the athletes run with the same speed.
Explanation:
In the whole process , kinetic energy is converted into potential energy .
1/2 m v² = mgh
v² = 2gh
h = v² / 2g
In this expression we see that height attained does not depend upon mass of the object . At the same time it also makes it clear that it depends upon velocity . As the velocity in both the cases are same , height attained by both of them will be same. Hence option d ) is correct.
Answer:
3.33 Joules Per Second
Explanation:
Before finding the Power, we need to calculate the Work Done. The Work Done can be calculated using the formula:
WD = F × d
where F is the Magnitude of Force in <em>N</em>
<em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em>d is the Parallel Distance moved by the object in <em>m</em><em>.</em>
Hence, by Applying this formula, we get:
WD = (5)(20)
= 100 J
From here calculating Power is simple as it is the Rate of Work Done. Hence,
Power = 100/30
= <u>3</u><u>.</u><u>3</u><u>3</u><u> </u><u>J</u><u>/</u><u>s</u>
Therefore, the power put out is <u>3</u><u>.</u><u>3</u><u>3</u><u> </u><u>J</u><u>o</u><u>u</u><u>l</u><u>e</u><u>s</u><u> </u><u>p</u><u>e</u><u>r</u><u> </u><u>S</u><u>e</u><u>c</u><u>o</u><u>n</u><u>d</u><u>.</u>