Average speed of the runner is the rate at which the runner covers the total distance. Average speed of the runner in the race is given by,
Average speed = 
Where
Total distance = Distance covered by the runner from initial to final position
Total time = time taken by the runner to cover entire distance
Instantaneous speed is the speed of the runner at the particular moment in the given time. Instantaneous speed is given by,
Instantaneous speed = 
x = position of the runner at time t
t = time taken to cover distance x
Hence, Average speed and instantaneous speed are different for a runner running in the race.
No force contributes to density, the density is a physical quantity that is defined as being

the raport between the mass of the object and its volume. However if you want to measure the density of an object you might want to determine its gravity force (weight)

from which knowing the gravitational acceleratin you can find its mass
where

is given in Newtons and

is given in
Reflecting telescopes are popular because they are more durable than a refracting telescopes.
There is a difference between these two types of telescopes, reflecting telescopes worked by reflecting light, they are also known as reflector and refracting telescopes worked by refracting light and they are also known as reflactor.
Reflecting telescopes also provides a good focus.
Answer:
1- The acceleration of the object is larger in magnitude the smaller the radius of the circle.
Explanation:
The acceleration of an object in a circular path is

As can be seen from the equation, if the radius of the circle is decreases, the magnitude of the acceleration increases.
As for the direction of the acceleration, it is always towards the center, and it is always perpendicular to the direction of the velocity.
The work done on the puck is 96 J
Explanation:
According to the work-energy theorem, the work done on the hockey puck is equal to the change in kinetic energy of the puck.
Mathematically:
where
is the final kinetic energy of the puck, with
m = 2 kg being the mass of the puck
v = 10 m/s is the final speed
is the initial kinetic energy of the puck, with
u = 2 m/s being the initial speed of the puck
Substituting numbers into the equation, we find the work done by the player on the puck:
Learn more about work and kinetic energy:
brainly.com/question/6763771
brainly.com/question/6443626
brainly.com/question/6536722
#LearnwithBrainly