Answer:
(d) 9 × 10^{3] J
Explanation:
from the question we are given the following:
weight of the man = 6.0 × 10 ^ {2} N
average speed (v) = 3 m/s
time (t) = 3 s
potential energy (U) = ?
We can calculate the increase in potential energy of the man by applying the formula below
increase in potential energy = P₂ - P₁
where
- P₁ is the initial potential energy
- P₂ is the final potential energy
- Potential energy = mass x acceleration due to gravity x height
From physic we know that weight = mass x acceleration due to gravity
- We should take note that the distance in this case is also our height, and we can get it from the formula distance = velocity x time
- Distance = 3 x 5 = 15 meters
- Initial potential energy P₁ is zero because the person was initially in motion and potential energy is the energy at rest.
therefore
potential energy = 6.0 × 10 ^ {2} × 15 = 9 × 10^{3] J
Density =Mass/volume
When mass is constant, density is inversely proportional to volume or vice versa
When volume decreases, density increases
Hope it helps
Answer:
The rotor's angular velocity is 82.73rad/s
Explanation:
It is a curvilinear movement of a constant radius. If there is uniform angular acceleration, then it is a circular motion with constant acceleration, whose equations are analogous to that of the translational motion.
Calculating the initial velocity of the rotor, V1 in rad/s
V1 = 610rev/minute × 6.28 × 1miute/60secs
V1 = 63.85rad/s
Using kinematic equation to calculate the final velocity of the rotor
Given:
Angular acceleration = 5.9rad/s^2
Time,t= 3.2seconds
V2 = V1 + a × t
V2 = 63.85 + (5.9)× (3.2)
V2 = 63.85 + 18.88
V2 = 82.73rads/s
Answer: The correct answer for this question is letter (B) The electromagnetic waves reach Earth, while the mechanical waves do not. The sun generates both mechanical and electromagnetic waves. Space, between the sun and the earth is a nearly vacuum. So mechanical wave can not spread out in the vacuum.
Hope this helps!
Answer: 0 m
Explanation:
Let's begin by stating clear that movement is the change of position of a body at a certain time. So, during this movement, the body will have a trajectory and a displacement, being both different:
The trajectory is the <u>path followed by the body</u> (is a scalar quantity).
The displacement is <u>the distance in a straight line between the initial and final position</u> (is a vector quantity).
According to this, in the description Matthew's home is placed at 0 on a number line, then he moves 10 m to the park (this is the distance between the park and Mattew's home), then 15 m to the movie theatre until he finally comes back to his home (position 0). So, in this case we are talking about the <u>path followed by Matthew</u>, hence <u>his trajectory</u>.
However, if we talk about Matthew's displacement, we have to draw a straight line between Matthew's initial position (point 0) to his final position (also point 0).
Now, being this an unidimensional problem, the displacement vector for Matthew is 0 meters.
