The expression for the frictional force between the sled and the ground is:

where

is the coefficient of friction, m is the mass of the object and

is the gravitational acceleration.
The friction force in our problem is F=80.85 N. The mass of the object is m=15 kg. Re-arranging the formula, we can find the value of k:
Answer:
The current on the water layer = 1.64×10^-3A
Explanation:
Let's assume that the radius given for the string originates from the centre of the string. The equation for determining the current in the water layer is given by:
I = V × pi[(Rwater + Rstring)^2 - (Rstring)^2/ ( Resitivity × L)
I =[ 166×10^6 ×3.142[(0.519×10^-4) + (2.15×10^-3])^2 - ( 2.15×10^-3)^2] / ( 183 × 831)
I =[ 521572000(4.848×10^6)- 4.623×10^-6]/ 154566
I = 252.83 -(4.623×10^-6)/ 154566
I = 252.83/154566
I = 1.64× 10^-3A
The car is not moving,or either it is going backwords
Answer:
v_f = 24.3 m / s
Explanation:
A) In this exercise there is no friction so energy is conserved.
Starting point. On the roof of the building
Em₀ = K + U = ½ m v₀² + m g y₀
Final point. On the floor
Em_f = K = ½ m v_f²
Emo = Em_g
½ m v₀² + m g y₀ = ½ m v_f²
v_f² = v₀² + 2 g y₀
let's calculate
v_f = √(10² + 2 9.8 25)
v_f = 24.3 m / s
<span> The meteor accelerates after it is brought into earths force field
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