The acceleration of the particle at time t is:

The velocity of the particle at time t is given by the integral of the acceleration a(t):

and the position of the particle at time t is given by the integral of the velocity v(t):

Assuming the particle starts from position x(0)=0 at t=0, the distance the particle covers in the first t=2 seconds can be found by substituting t=2 s in the equation of x(t):
Answer:
the car have travelled 0.31 mile during that time
Explanation:
Applying the Equation of motion;
s = 0.5(u+v)t
Where;
s = distance travelled
u = initial speed = 0 mph
v = Final speed = 50 mph
t = time taken = 3/4 min = 3/4 ÷ 60 hours = 1/80 hour
Substituting the given values into the equation;
s = 0.5(0+50)×(1/80)
s = 0.3125 miles
s ~= 0.31 mile
the car have travelled 0.31 mile during that time
Answer:
The value of the average convection coefficient is 20 W/Km².
Explanation:
Given that,
For first object,
Characteristic length = 0.5 m
Surface temperature = 400 K
Atmospheric temperature = 300 K
Velocity = 25 m/s
Air velocity = 5 m/s
Characteristic length of second object = 2.5 m
We have same shape and density of both objects so the reynold number will be same,
We need to calculate the value of the average convection coefficient
Using formula of reynold number for both objects



Here, 


Put the value into the formula


Hence, The value of the average convection coefficient is 20 W/Km².
12.5 times 14 and convert to meters its 1.75 meters per second