Answer:
the answer is A.) -1 * 10^3[N]
Explanation:
The solution consists of two steps, the first step is using the following kinematic equation:
![v=v_{i} +a*t\\where:\\v=final velocity [m/s]\\v_{i}=initial velocity [m/s]\\a=acceleration[m/^2]\\t=time[s]\\](https://tex.z-dn.net/?f=v%3Dv_%7Bi%7D%20%2Ba%2At%5C%5Cwhere%3A%5C%5Cv%3Dfinal%20velocity%20%5Bm%2Fs%5D%5C%5Cv_%7Bi%7D%3Dinitial%20velocity%20%5Bm%2Fs%5D%5C%5Ca%3Dacceleration%5Bm%2F%5E2%5D%5C%5Ct%3Dtime%5Bs%5D%5C%5C)
The initial velocity is 10 [m/s], and the final velocity is zero because the car stops in 0.5[s].
Replacing:
![0=10+a*(0.5)\\a=-20[m/s^2]](https://tex.z-dn.net/?f=0%3D10%2Ba%2A%280.5%29%5C%5Ca%3D-20%5Bm%2Fs%5E2%5D)
Now in the second part, we need to use the second law of Newton, this law relates the forces with the acceleration of a body.
In the moment when the car stops suddenly the driver will feel the force of the seatbelt acting in the opposite direction of the movement.
![F=m*a\\F=50[kg]*(-20[m/s^2])\\units\[kg]*[m/s^2]=[N]\\F=-1000[N] or -1*10^{3} [N]](https://tex.z-dn.net/?f=F%3Dm%2Aa%5C%5CF%3D50%5Bkg%5D%2A%28-20%5Bm%2Fs%5E2%5D%29%5C%5Cunits%5C%5Bkg%5D%2A%5Bm%2Fs%5E2%5D%3D%5BN%5D%5C%5CF%3D-1000%5BN%5D%20or%20-1%2A10%5E%7B3%7D%20%5BN%5D)
The minus sign means that the force is acting in the opposite direction of the movement.
This is false. I hope this helps.
To solve this problem it is necessary to apply the concepts related to the kinematic equations of movement description, which determine the velocity, such as the displacement of a particle as a function of time, that is to say
Where,
x = Displacement
v = Velocity
t = Time
Our values are given as,
Replacing we have that,
Therefore the distance from Earth to the Moon is 399.000 km
Acceleration is the
rate of change of velocity, a body moving with uniform velocity does not
possess acceleration at all i.e. acceleration is zero
The answer to question one is A.
The answer to question two is A.
The answer to question three is D.
