m = mass of the person = 82 kg
g = acceleration due to gravity acting on the person = 9.8 m/s²
F = normal force by the surface on the person
f = kinetic frictional force acting on the person by the surface
μ = Coefficient of kinetic friction = 0.45
The normal force by the surface in upward direction balances the weight of the person in down direction , hence
F = mg eq-1
kinetic frictional force on the person acting is given as
f = μ F
using eq-1
f = μ mg
inserting the values
f = (0.45) (82) (9.8)
f = 361.6 N
Answer:
d A ball is rolling down an inclined plane.
Explanation:
When path length is equal to the displacement
then we can say that the motion of the object must be in straight line so that the distance and displacement must be same
SO here we can say
a A ball on the end of a string is moving in a vertical circle.
In circular path distance and displacement is not same
b A toy train is traveling around a circular track.
In circular path distance and displacement is not same
c A train travels 5 miles east before it stops. It then travels 2 miles west.
Net displacement is 3 miles East while distance is 7 miles
d A ball is rolling down an inclined plane.
Here its motion is in straight line so we can say that path length and displacement will be same
e A ball rises and falls after being thrown straight up from the earth's surface.
In this type of to and fro motion path length is not same as displacement
Answer:
Change in electric potential energy ∆E = 365.72 kJ
Explanation:
Electric potential energy can be defined mathematically as:
E = kq1q2/r ....1
k = coulomb's constant = 9.0×10^9 N m^2/C^2
q1 = charge 1 = -2.1C
q2 = charge 2 = -5.0C
∆r = change in distance between the charges
r1 = 420km = 420000m
r2 = 160km = 160000m
From equation 1
∆E = kq1q2 (1/r2 -1/r1) ......2
Substituting the given values
∆E = 9.0×10^9 × -2.1 ×-5.0(1/160000 - 1/420000)
∆E = 94.5 × 10^9 (3.87 × 10^-6) J
∆E = 365.72 × 10^3 J
∆E = 365.72 kJ
Answer: 15.29
Explanation: there you go have a nice day (*^p^*)
Answer:
b. They orbit around the Sun in a counterclockwise direction, when viewed from above the ecliptic plane.
Explanation:
All the objects of the solar system revolve around the Sun in a counterclockwise direction. The comet coming from the Oort's cloud will also follow the same kind of orbit. That is why it can't be a property to distinguish an Oort's cloud comet.
All other properties are correct to identify an Oort's cloud comet as the Oort's cloud is a considered a spherical cloud just outside the Solar system.
