Answer:
a.) 600N
b.) 2 m/s^2
Explanation:
a.)
In order to solve for the needed force, you must use Newton's 2nd law which states that a force is equal to mass multiplied by acceleration.
Basically: Force = mass * acceleration ; F = ma
Since both mass and acceleration are already given, just plug them into the formula and solve for force:
Mass = 200kg
Acceleration = 3m/s^2
F = m * a = 200 * 3 = 600kg * m/s^2 = 600N
b.)
In order to find the acceleration, like the hint already says, you need to find the net force first and then use Newton's 2nd law.
To calculate net force:
Since both forces are parallel (affect the same axis) and in opposite directions, you can subtract the two in order to find resultant magnitude. The resultant direction is the direction of the force with the large magnitude.
Net Force: 8N - 4N = 4N
Net Force Direction: since 8N > 4N, the direction is in the same direciton as the 8N force = Left
Finally, you find acceleration using newton's 2nd law, F = ma.
Since you already know mass and net force, plug in to solve for acceleration:
4N = 2kg * a
a = 4 N / 2kg = 2m/s^2