Answer:
The equatiom of kinetic energy is 1/2×m×v² where m represents mass and v is velocity :
The unit for kinetic energy is measured in Joules (J).
A) For upward projection.
v = u -gt
but v = 0, thus u = gt,
t = u/g, t= 7.83/9.81, t = 0.798 sec
Therefore, distance, s
S = ut -1/2gt²
= 7.83(0.798) - 1/2(9.81)(0.798²)
= 6.248 - 3.124
= 3.124 m
Total Height is 10.3 + 3.124 = 13.424 m
For the case of free fall
s= ut + 1/2 gt² but u =0
s = 1/2 gt²
t² = (2 × 13.424)/9.81
t² = 2.7368
t = 1.654 s
Therefore, the time the stone remains in air will be 1.654 + 0.798
= 2.452 seconds
b) Speed of the impact on the ground
v= u + gt but, u = 0
thus v = gt
therefore, v = 9.81 × 1.653
= 16.216 m/s
Answer:
A) No work was done on the box.
Explanation:
Answer:
Explanation:
Given that,
Mass of a uniform rod, m = 12 kg
Length of the rod, l = 0.3 m
The moment of inertia rotating about an axis perpendicular to the rod and passing through the center of the rod is given by :
So, the moment of inertia of the rod is
Answer:
d = 186.3 m
Explanation:
Given that,
Speed of Matthew 3.45 m/s due eastward
It takes 54 seconds to walk to the store.
We need to find the distance covered. The product of speed and time is equal to the distance covered.
d = vt
Putting all values,
d = 3.45 m/s × 54 s
d = 186.3 m
Hence, he will cover a distance of 186.3 m.