Answer:
The coefficient of kinetic friction between the puck and the ice is 0.11
Explanation:
Given;
initial speed, u = 9.3 m/s
sliding distance, S = 42 m
From equation of motion we determine the acceleration;
v² = u² + 2as
0 = (9.3)² + (2x42)a
- 84a = 86.49
a = -86.49/84
|a| = 1.0296
= ma
where;
Fk is the frictional force
μk is the coefficient of kinetic friction
N is the normal reaction = mg
μkmg = ma
μkg = a
μk = a/g
where;
g is the gravitational constant = 9.8 m/s²
μk = a/g
μk = 1.0296/9.8
μk = 0.11
Therefore, the coefficient of kinetic friction between the puck and the ice is 0.11
D. Mechanical waves need to have a medium
Answer:
c will have the largest charge
Explanation:
because more lines are coming more line means more foce is required
Answer:
v = 4.58 m/s
Explanation:
In order to calculate the speed of the skier when she gets the bottom of the hill, you have to calculate the speed of the skier when she crosses the rough patch.
To calculate the velocity at the final of the rough patch you take into account that the work done by the friction surface is equal to the change in the kinetic energy of the skier:
(1)
Where the minus sign means that the work is against the motion of the skier.
Wf: friction force
m: mass of the skier = 65.0kg
N: normal force = mg
g: gravitational acceleration = 9.8m/s^2
d: distance of the rough patch = 4.00m
v: speed at the end of the rough patch = ?
vo: initial speed of the skier = 6.85m/s
μk: coefficient of kinetic friction = 0.330
You replace the expression for the normal force in the equation (1), and solve for v:
Then, the speed fot he skier at the bottom of the hill is 4.58m/s
Physical changes do not change the identity of the substance. Heat causes chemical reactions. You cannot see chemical changes with the naked eye. The identity of a substance changes like when you burn paper, from paper it turns into ash and produces smoke, which are products from the chemical reactions.