Answer:
F = 7500 N
Explanation:
given,
mass of the car, m = 1200 Kg
initial speed of the car, v = 25 m/s
final speed of car = 0 m/s
time in which car is at rest, t = 5 s
distance = 50 m
Force = ?
using equation of motion for the calculation of acceleration.
v² = u² + 2 a s
0² = 25² + 2 x a x 50
100 a = -625
a = - 6.25 m/s²
negative sign shows deceleration of the car
now, force calculation
F = m a
F = 1200 x 6.25
F = 7500 N
hence, net force is equal to F = 7500 N
The age of a man whose normal blood pressure measures 123 mm of hg
9 years
<h3>What is Quadratic equation ?</h3>
A quadratic equation as an equation of degree 2, meaning that the highest exponent of this function is 2. The standard form of a quadratic equation is y = a
+ bx + c, where a, b, and c are numbers and a cannot be 0
P(A) = 0.006 
- 0.02a + 120
123 = 0.006- 0.02a + 120
0=0.006 - 0.02a - 3
you can use the quadratic equation formula to solve for the man's age.
A = (-b ± (
) ) / (2a)
A = (0.02 ± 
/ (2*0.006)
A = (0.02 ± 
) / 0.012
A = 9 , -5.67
Age of the man will be 9 years
To learn more about quadratic equation here
brainly.com/question/17177510?referrer=searchResults
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They can't hear an echo in small room because in it the sound can't be reflected back. For an echo of a sound to be heard,the minimum distance between the source of sound and the walls of the roomshould be 17.2 m. Obviously,in asmall room echoes cannot beheard.
Tension in the rod is responsible for balancing force due to gravity.
The correct answer is:
<span>A. electron attraction between electron and nucleus = centripetal force of the orbiting electron
In fact, Bohr model depicts the atom as a nucleus surrounded by electrons in circular orbit around it, similar to the planets around the Sun. The centripetal force that keeps the electrons in circular motion around the nucles is provided by the electrostatic force between the electrons and the nucleus, so option A is the correct one.</span>
