That was Tycho Brahe, and I thought it was actually more years than that.
Answer:
In most materials, as heat energy is absorbed, the density decreases. IF a certain object is heated, it might appear bigger than usual because it expands as the molecules inside moves faster than usual. However the mass of it stays the same while the density decreases.
Answer: -0.84 rad/sec (clockwise)
Explanation:
Assuming no external torques act on the system (man + turntable), total angular momentum must be conserved:
L1 = L2
L1 = It ω + mm. v . r = 81.0 kg . m2 .21 rad/s – 56.0 kg. 3.1m/s . 3.1 m
L1 = -521.15 kg.m2/sec (1)
(Considering to the man as a particle that is moving opposite to the rotation of the turntable, so the sign is negative).
Once at rest, the runner is only a point mass with a given rotational inertia respect from the axis of rotation, that can be expressed as follows:
Im = m. r2 = 56.0 kg. (3.1m)2 = 538.16 kg.m2
The total angular momentum, once the runner has come to an stop, can be written as follows:
L2= (It + Im) ωf = -521.15 kg.m2/sec
L2= (81.0 kg.m2 + 538.16 kg.m2) ωf = -521.15 kg.m2/sec
Solving for ωf, we get:
ωf = -0.84 rad/sec (clockwise)
Answer:
0.11 m/s
Explanation:
From the question given above, the following data were obtained:
Initial displacement (d1) = 1.09 m
Final displacement (d2) = 2.55 m
Time (t) = 12.8 s
Average velocity =?
Next, we shall determine the total displacement (i.e change in displacement). This can be obtained as follow:
Initial displacement (d1) = 1.09 m
Final displacement (d2) = 2.55 m
Total displacement = d2 – d1
Total displacement = 2.55 – 1.09
Total displacement = 1.46 m
Finally, we shall determine the average velocity of the beetle. This can be obtained as follow:
Total Displacement = 1.46 m
Total time (t) = 12.8 s
Average velocity =?
Average velocity = Total Displacement / Total time
Average velocity = 1.46/12.8
Average velocity = 0.11 m/s
Thus, the average velocity of the beetle is 0.11 m/s
