Explanation:
(a) Displacement of an object is the shortest path covered by it.
In this problem, a student is biking to school. She travels 0.7 km north, then realizes something has fallen out of her bag. She travels 0.3 km south to retrieve her item. She then travels 0.4 mi north to arrive at school.
0.4 miles = 0.64 km
displacement = 0.7-0.3+0.64 = 1.04 km
(b) Average velocity = total displacement/total time
t = 15 min = 0.25 hour

Hence, this is the required solution.
Answer:
Value of magnitude of acceleration will be 
Explanation:
It is given that when a stone is dropped it takes 2.2 sec to reach the ground
(a) As the stone is dropped from the top of building
So its initial velocity
will be 0 m /sec
(b) As the stone is free falling and there is no external force applied on it so its acceleration will be equal to acceleration due to gravity
So value of magnitude of acceleration will be equal to
Given:
• Mass, m = 0.200 mg
,
• Speed, v = 3.00 x 10³ m/s
,
• Time, t = 6.00 x 10^⁻⁸ s.
Let's calculate the force exerted.
Using the inpulse-momentum theroerm, we have:
impulse = change in momemntum
Where:
Impulse = force x time
change in momentum = mass x velocity.
Thus, we have:

Let's solve for the force F:

Therefore, the force exterted is 10000 N.
ANSWER:'
10000 N
Answer:

Explanation:
First calculate the mass of the asteroid. To do so, you need to find the volume and know the density of iron.
If r = d/2 = 645ft, then:


In order to find force, use Newton's universal law of gravitation:

Where,
G= the gravitational constant:

