Answer:
KE = 100 J
Explanation: Should be correct
V=(40km/hr)(hr/3600s)(1000000mm/km)
v=11111.1mm/s
v=d/t
d=vt
d=(11111.1mm/s)(5s)
d=55555mm
d=5.56x10^4mm
Before coming into conclusion first we have to understand both scalar and vector .
A scalar quantity is a physical quantity which has only magnitude for it's complete specification.
A vector quantity is that physical quantity which not only requires magnitude but also possesses direction for it's complete specification.
So the most important factor that differentiate vector from scalar is the direction.
As per the question the student is doing an experiment where he is recording the data obtained during the process.
In order to arrange them in data table, he should ask about the direction of the quantity under consideration.
Hence the correct option is the third option(C)i.e does the measurement include direction?
Answer:
N = 6.67 N
Explanation:
The frictional or frictional force is a force that arises from the contact of two bodies and opposes movement.
The friction is due to imperfections and roughness, mainly microscopic, that exist on the surfaces of the bodies. Upon contact, these roughnesses engage with each other making movement difficult. To minimize the effect of friction, either the surfaces are polished or lubricated, since the oil fills the imperfections, preventing them from snagging.
As the frictional force depends on the materials and the force exerted on one another, its magnitude is obtained by the following expression:
f = μ*N Formula (1)
where:
f is the friction force (N)
μ is the coefficient of friction
N is the normal force (N)
Data
f = 0.2 N : frictional force between the steel spatula and the Oiled Steel frying pan
μ = 0.03 :coefficient of kinetic friction between the two materials
Calculating of normal force
We replace data in the formula (1)
f = μ*N
0.2 = 0.03*N
N = 0.2 / 0.03
N = 6.67 N
It holds more weight in the regular water.