What would be the final velocity for an airplane that starts at the beginning of a 4km runway with an initial velocity of 60 km/h accelerating at 1.2×104 km/h^2 if the pilot uses the entire runway before liftoff? A. 22.5×10^5 B. 1.0×10^5 C. 3.16×10^2 D. 9.6×10^4 PLEASE HELP I KEEP GETTING THE WRONG ANSWER

2.12×10^-2hour

Explanation:

Acceleration is defined as the change in velocity of a body with respect to time.

Using one of the equations of motion:

S = ut + 1/2at²

Where S is the distance traveled by the airplane

u is the initial velocity

a is its acceleration

t is the time of travel

Given a = 1.2×104 km/h²

u = 60km/hr

t= ?

S = 4km

Substituting the values given into the formula to get 't'

4 = 60t+1/2(1.2×10⁴)t²

4 = 60t+0.6×10⁴t²

0.6×10⁴t²+60t-4= 0

Factorizing the quadratic equation

t = -b±√b²-4ac/2a

Where a= 6000 b = 60 c = -4

t = -60±√60²-4(6000)(-4)/2(6000)

t = -60±√3600+96000/12000

t = -60±√99600/12000

t = -60±315.6/12000

t = -60+315.6/12000

t= 255.6/12000

t = 0.0212hour

t = 2.12×10^-2hour

if you already have the answer to (a), then just work out how many periods there are in 1 minute, and that's the answer to (c).

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation: