Question

I need to answer all that question give me the answer plese (with short answers)

I.

1- Explain why velocity, but no speed, is a vector

2- Describe how to use a vector to represent the velocity of a moving object.

3- State the difference between velocity and acceleration

4-What happens to your body when in a moving car, it suddenly accelerates

5-What happens to your body when in a moving car, it suddenly decelerates

6- What is the formula to find acceleration given the time and distance of the object

II.

1. A car accelerates from 5.0 m/s to 22 m/s in 18 seconds.
a) Find the acceleration.
b) Find the displacement travelled during that time.

2. How far does a cyclist travel when she accelerates from rest to 6.5 m/s in 22 s?

3. A child coasting on a bicycle slowly decelerates from 5.5 m/s to 2.4 m/s in 42 seconds. Determine the distance (displacement) he travels during that time.

4. A small aircraft, upon landing, can decelerate from 122 km/h to rest in 7.2 s. What length of runway does he need to come to a full stop?

5. A car initially travelling with a velocity of 8.0 m/s accelerates to 24 m/s in a distance (displacement) of 124 m. How long did it take to accelerate over this distance?

Answer 1

I Speak English In A Medium Level.

1) The Velocity Is A Vector Because Has Direction And Module, And The Speed Has Only Module... Example: A Car Moving In A Velocity Of 30m/s Around North.

2) A Object Moving To A Velocity Of 50m/s Around North But The Friction Of Air Does The Object Moving To 40m/s Around West, Find Its Vector Velocity.
V= Raiz (50m/s)^2 + (40m/s)^2
V= Raiz 2500m/s + 1600m/s
V= Raiz 4100m/s
V= 64,03m/s

3) Time...
aceleration= Delta Velocity/ Time
Time= Vf - Vi / a

4) Your Body Bow Toward Back

5) Your Body Bow Toward Ahead

6) Here We Can Know The Velocity With The Distance And The Time
a= Delta Velocity/ Time...

II
1. a) Vf= 22m/s; Vi= 5m/s; t= 18s
a= 22m/s - 5m/s /18s
a= 17m/s / 18s
a= 0,94m/s^2
The Car Accelerates 0,94m/s^2 In 18 Seconds
b) Displacement...
d= t (Vi + Vf)/2
d= 18s (5m/s + 22m/s)/2
d= 18s (27m/s)/2
d= 18s (13,5m/s)
d= 243metters

2) a= 6,5m/s - 0/ 22s
a= 0,29m/s^2 ---> Acceleration
Distancia...
d= 22s (6,5m/s)/2
d= 22s (3,25m/s)
d= 71,5m ---> Distance

3)Vi= 5,5m/s; Vf= 2,4m/s; t= 42s
d= t (Vi+Vf)/2
d=42s ( 5,5m/s - 2,4m/s)/2
d= 42s (3,1m/s)/2
d= 42s (1,55m/s)
d=65,1 m

4) 122Km/h ---> m/s
122Km/h (1000m/1Km) (1h/3600s)
33,88m/s
d= 7,2s (33,88m/s)/2
d= 7,2s (16,94m/s)
d=121,96m
The Small Aircraft Needs 121,86m For Come To Rist

5) We Find The Time... With Vf=24m/s; Vi= 8m/s; Distance= 124m
d= t (Vf+Vi)/2
124m= t (8m/s + 24m/s)/2
124m / 16m/s = t
t= 7,75s ---> The Car Delay 7,75s In Travel 124m...
Now Find The Acceleration
a= Vf-Vi / t
a= 24m/s -8m/s / 7,75s
a= 16m/s / 7,75s
a=2,06m/s^2---> The Car Needs An Acceleration Of 2,06m/s^2 For Travels 124m In 7,75s

Good Luck!