Sports like swimming and track are individual races but in the end everyone on the team races come together to make a team placement.
Answer:
The coefficient of kinetic friction = 0.026
Explanation:
An 56 kg sled is being pulled across the snow, at constant speed,by a horizontal force of 15 N.
Here we have to note that the weight is pulled at a constant speed . This means that the net force acting on the weight is zero.
The external force acting on the body is in the forward direction and the friction acts in the backward direction.
Friction increases as the mass of the body increases.
Friction = 
We now equate this to the external force of 15 N.
15 = 
= 
= 0.026
The coefficient of kinetic friction = 0.026
Answer:
The magnitude of the change in momentum of the stone is 5.51kg*m/s.
Explanation:
the final kinetic energy = 1/2(0.15)v^2
1/2(0.15)v^2 = 70%*1/2(0.15)(20)^2
v^2 = 21/0.075
v^2 = 280
v = 16.73 m.s
if u is the initial speed and v is the final speed, then:
u = 20 m/s and v = - 16.73m/s
change in momentum = m(v-u)
= 0.15(- 16.73-20)
= -5.51 kg*m.s
Therefore, The magnitude of the change in momentum of the stone is 5.51kg*m/s.
Answer:
A.) 230 km
B.) 76.67 km/h
Explanation:
Given that On a straight road (taken to be in the +x direction) you drive for an hour at 50 km per hour, then quickly speed up to 90 km per hour and drive for an additional two hours.
A.) How far do you go?
When driving for an hour, the distance covered will be
Distance = speed × time
Distance = 50 × 1 = 50 km
When driving for additional 2 hours, the distance covered will be
Distance = 90 × 2 = 180 km
Total distance = 180 + 50 = 230 km
b. What is your average x component of velocity?
Average Velocity = total distance/ total time
Average velocity = 230/3
Average velocity = 76.67 km/h
c. Why isn't vavg,x equal to the arithmetic average of your initial and final values of vx, (50+90)/2 = 70 km per hour
They are not equal because of the displacement is the same as distance travelled.
