Pushing a broke down car, even done by more than one person, is difficult especially if the distance to be covered is quite far. A car is heavy and it requires a lot of force to start the car moving. This is because the inertia of the car to remain at rest is great. Additionally, the force applied in pushing the car must be greater than the frictional force to cause it to accelerate. The frictional force is dependent on the mass of the object which means that the frictional force acting on the car is also great. Finally, with every push of the car, the frictional force will always be present and acting on the opposite direction. The push that will be supplied must be sustained all throughout.
Answer:
human body is answer according to our studies
(a) The spring stiffness constant of the spring is 18,392 N/m.
(b) The time the car was in contact with the spring before it bounces off in the opposite direction is 0.23 s.
<h3>Kinetic energy of the car</h3>
The kinetic energy of the car is calculated as follows;
K.E = ¹/₂mv²
K.E = ¹/₂ x 950 x 22²
K.E = 229,900 J
<h3>Stiffness constant of the spring</h3>
The stiffness constant of the spring is calculated as follows;
K.E = U = ¹/₂kx²
k = 2U/x²
k = (2 x 229,900)/(5)²
k = 18,392 N/m
<h3>Force exerted on the spring</h3>
F = kx
F = 18,392 x 5
F = 91,960 N
<h3>Time of impact</h3>
F = mv/t
t = mv/F
t = (950 x 22)/(91960)
t = 0.23 s
Learn more about spring constant here: brainly.com/question/1968517
#SPJ4
Answer:
l= 4 mi : width of the park
w= 1 mi : length of the park
Explanation:
Formula to find the area of the rectangle:
A= w*l Formula(1)
Where,
A is the area of the rectangle in mi²
w is the width of the rectangle in mi
l is the width of the rectangle in mi
Known data
A = 4 mi²
l = (w+3)mi Equation (1)
Problem development
We replace the data in the formula (1)
A= w*l
4 = w* (w+3)
4= w²+3w
w²+3w-4= 0
We factor the equation:
We look for two numbers whose sum is 3 and whose multiplication is -4
(w-1)(w+4) = 0 Equation (2)
The values of w for which the equation (2) is zero are:
w = 1 and w = -4
We take the positive value w = 1 because w is a dimension and cannot be negative.
w = 1 mi :width of the park
We replace w = 1 mi in the equation (1) to calculate the length of the park:
l= (w+3) mi
l= ( 1+3) mi
l= 4 mi
-- The resistance of the heater is (volts/current) = 5 ohms
-- The heating (RMS) value of a sinusoidal AC is V(peak)/√2 . For this particular alternator, V(peak)=100V, so the heating (RMS) equivalent is 70.71 V.
-- The heating power delivered to the electric heater is (E²/R).
Power = (100/√2)² / 5
Power = 5,000 / 5
<u>Power = 1,000 watts </u>
