Speed (velocity)=distance/time
V1=98km/4hr=24.5km/hr
V2=61km/3hr=20.3km/hr
Average speed (velocity)=total velocity/ number
Average speed (velocity)=44.8km/hr/2=22.4
So the average speed is 22.4km/hr
Answer:
The length of the rod should be

Explanation:
Period of simple pendulum is given by

We have

The length of the rod should be

Kinetic energy , KE= [1/2]m*v^2
m = 10 kg
v=20m/s
KE = [1/][(10kg)(20m/s)^2 = [1/2](10kg)(400m^2/s^2) = 2000 joule
Answer: 2000 joule
Given that,
Mass of trackler, m₁ = 100 kg
Speed of trackler, u₁ = 2.6 m/s
Mass of halfback, m₂ = 92 kg
Speed of halfback, u₂ = -5 m/s (direction is opposite)
To find,
Mutual speed immediately after the collision.
Solution,
The momentum of the system remains conserved in this case. Let v is the mutual speed after the collision. Using conservation of momentum as :

So, the mutual speed immediately after the collision is 1.04 m/s but in opposite direction.