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:
The thermal energy is carried by electromagnetic waves
Explanation:
There are three types of transfer of heat (thermal energy):
- Conduction: conduction occurs when two objects/two substances are in contact with each other. The heat is transferred from the hotter object to the colder object by the collisions between the molecules of the two mediums.
- Convection: convection occurs when a fluid is heated by an external source of heat. The part of the fluid closer to the heat source gets warmer, therefore it becomes less dense and it rises, and it is replaced by the colder part of the fluid, which is colder. Then, this part of fluid is heated as well, so it gets warmer, it rises, etc.. in a cycle.
- Radiation: radiation occurs when thermal energy is carried by electromagnetic waves. Since electromagnetic waves do not need a medium to propagate, this is the only method of heat transfer that can occur through a vacuum (so, in space as well).
Indeed, the Sun emits a lot of electromagnetic radiation, which travels through space and eventually reaches the Earth, heating it.
1). trajectory
2). person sitting in a chair
3). 490 meters
4). 65 m/s
5). False. The projectile's displacement, velocity, and acceleration have vertical and horizontal components, but the projectile doesn't.
6). False
7). The vertical component of a projectile doesn't change due to gravity, but the vertical components of its displacement, velocity, and acceleration do.
The vertical components do NOT equal the horizontal components.
8). Decreasing if you include the effects of air resistance. Constant if you don't. Gravity has no effect on horizontal velocity.
9). We can't see the simulation. But if the projectile doesn't have jets on it, then as it travels upward, its vertical velocity must decrease, because gravity is trying to not let it get away.
10). We can't see the simulation. But if the projectile is traveling downward, we would call that "falling", and its vertical velocity must increase, because gravity is pulling it downward.
Answer:
is the "momentum" of the given moving object.
Explanation:
"Momentum" of an object is defined as the "velocity" changed by an object by moving the object from "one place" to "another place". The "Momentum" of an object is represented as "". It is the product of the "mass of object" and the "velocity of object". It is mathematically written as .
Where, "m" is mass of object and "v" is velocity of object.
Given that,
Mass of an object is 25 Kg.
Velocity of an object is 25 m/s.
Now, to calculate momentum of the given object us the formula .
Plug the values,