The second runner must run 3.3m/s. If the leading runner is 1.5 seconds ahead and there are 30m left, the second runner would need to run slightly faster than the lead in order to finish at the same time. To calculate this I did 30/1.5 which gave me 0.05. I added this onto the speed of the lead runner to get 3.3m/s :)
Answer:
a. 3 m/s
Explanation:
The magnitude of the momentum of an object is given by:
where
m is the mass of the object
v is the speed of the object
For the ball in this problem, we know:
p = 12 kg m/s is the momentum
m = 4 kg is the mass
Solving the equation for v, the speed, we find:
Answer:
1.287m/s
Explanation:
Using the law of conservation of mass expressed as;
m1u1+m2u2 = (m1+m2)v
m1 and m2 are the masses of the objects
u1 and u2 are the velocities
v is the speed of the center of mas of the two carts
Given
m1 = 320g = 0.32kg
u1 = 1.25m/s
m2 = 270g = 0.27kg
u2 = 1.33m/s
Substitute this value into the formula and get v;
0.32(1.25)+0.27(1.33) = (0.32+0.27)v
0.4+0.3591 = 0.59v
0.7591 = 0.59v
v = 0.7591/0.59
v = 1.287m/s
hence the speed of the center of mass of the two carts is 1.287m/s