The average speed is a scalar quantity. The average speed of the skier is 10 km/hrs.
<h3>
What is the average speed?</h3>
It is calculated by dividing the total distance by the total time elapsed.
The

Where,
= average velocity
= displacement = 7.5 km
= change in time = 45 min = 0.75 hours
Put the values in the formula,

Therefore, the average speed of the skier is 10 km/hrs.
Learn more about average speed:
https://brainly.in/question/32459982
It will stay in motion unless an outside force slows it down.
In order to create a charged object you need to transfer electrons either away or to the object by induction, conduction, or friction
Induction is without contact(like bringing a charged object to a electroscope charges the leaves at the bottom)
Conduction is with contact(like the previous answer, wore touching transfers the charge from a source to the object)
Friction(rubbing a balloon on wool)
Answer:
We know that for a pendulum of length L, the period (time for a complete swing) is defined as:
T = 2*pi*√(L/g)
where:
pi = 3.14
L = length of the pendulum
g = gravitational acceleration = 9.8 m/s^2
Now, we can think on the swing as a pendulum, where the child is the mass of the pendulum.
Then the period is independent of:
The mass of the child
The initial angle
Where the restriction of not swing to high is because this model works for small angles, and when the swing is to high the problem becomes more complex.