<u>Answer:</u>
Positive acceleration is in third hour and negative acceleration is in second hour.
<u>Explanation:</u>
Velocity of car in first hour = 70 mph
Velocity of car in second hour = 60 mph
Velocity of car in third hour = 80 mph
Acceleration = Change in velocity / Time
Acceleration in second hour = (60 - 70)/1 = -10 mph²
Acceleration in third hour = (80 - 60)/1 = 20 mph²
So positive acceleration is in third hour and negative acceleration is in second hour.
Many things can affect a material's resistance, The type of material, how the material is being held (If its laying flat, being pulled, etc). What the material is used for, and how much material there is. Hope this helps!
Answer:
valves
The heart has four valves - one for each chamber of the heart. The valves keep blood moving through the heart in the right direction.
As per the question, the velocity of the airplane [v] = 660 miles per hour.
The total time taken by airplane [t] = 3.5 hours.
We are asked to determine the total distance travelled by the airplane during that period.
The distance covered [ S] by a body is the product of velocity with the time.
Mathematically distance covered = velocity × total time
S = v × t
= 660 miles/hour ×3.5 hours
= 2310 miles.
Hence, the total distance travelled by the airplane in 3.5 hour is 2310 miles.