Answer:
<h3>25km/hr</h3>
Explanation:
Velocity is the change in displacement of a body with respect to time.
Velocity - Displacement/time
Given
displacement = 76km
Time = 3hours
Substitute the given parameters into the formula;
Velocity = 75km/3hrs
Velocity = 25km/hr
Hence the velocity of the narwhal is 25km/hr
Answer:
a. A baseball after it has been hit - not in free fall
b. A rock that is thrown in the air - not in free fall
c. The moon - free-fall
d. A paper airplane - not in free fall
e. A bird flying - not in free fall
Explanation:
- The free-fall is defined as the falling of an object due to the action of gravity. The object is not experiencing any other force neglecting the air resistance.
- If an object is in free-fall, the direction of its motion is directed towards the center of the earth. It does not have a horizontal component of velocity.
- If the body is under free-fall, but a centripetal force acts on it where it is equal to the gravitational force at that point. The object will have two components of velocity along the tangential line, perpendicular to the radius of the orbit.
a. A baseball after it has been hit - not in free fall according to point 1 & 2.
b. A rock that is thrown in the air - not in free fall according to point 1.
c. The moon - free-fall according to point 3.
d. A paper airplane - not in free fall according to point 1 & 2.
e. A bird flying - not in free fall according to point 1 & 2.
Answer:
Sherpas do work that is much more meaningful than the work other climbers do.
Explanation:
Answer:
d) v1 = v2 = v3
Explanation:
This can be answered using conservation of energy. We calculate the mechanical energy E=K+U (sum of kinetic and gravitational potential energies) at the original and final points, and impose they are equal.
At the original point we have, for the three balls:

At the final point we have, for the three balls:

Since we have
, and
is the same for all balls, then
is the same for all balls, which means that
, the final velocity, is the same for all balls.