The last choice is your answer, I just did it.
Answer:
25J
Explanation:
Given parameters:
Mass of the watermelon = 2kg
Speed before touching the ground = 5m/s
Unknown:
Kinetic energy = ?
Solution:
To solve this problem, we must understand that kinetic energy is the energy possessed by a body in motion.
K.E = m v²
m is the mass
v is the velocity
Now, insert the parameters and solve;
K.E = x 2 x 5² = 25J
C is the answer because contact force, is the only force mentioned that opposes the motion of the rock
Answer:
<em>The block moves at 1.25 m/s</em>
Explanation:
<u>Law Of Conservation Of Linear Momentum
</u>
It states the total momentum of a system of bodies is conserved unless an external force is applied to it. The formula for the momentum of a body with mass m and speed v is
P=mv.
If we have a system of two bodies, then the total momentum is the sum of the individual momentums:
If a collision occurs and the velocities change to v', the final momentum is:
Since the total momentum is conserved, then:
P = P'
Or, equivalently:
The bullet of m1=0.049 kg moves at v1=421 m/s. Then it strikes a wooden block of m2=4.7 kg originally at rest (v2=0).
After the collision, the bullet continues at v1'=301 m/s. The speed of the block can be calculated by solving for v2':
Calculating:
The block moves at 1.25 m/s
Answer: d = 2,079 m
Explanation:
5.5 m/s(6.3 min)(60 s/min) = 2,079 m