a 700 N man stands on a scale on the floor of an elevator. The scare records the force it exerts on whatever is on it. What is the scale reading if the elevator has an acceleration of 1.8 m/s squared up ? I need help with what formula (s) to use to get the answer. I didn't understand the answer when I plugged in the numbers.

f=m (g+a)
f= 700 (9.81 + 1.8)

help..... not sure what to do

you have to enter mass for m.

700N is not mass, but weight.
mass= 700/9.8 kg

To find the scale reading in this scenario, we need to use Newton's second law of motion, which states that force (F) is equal to mass (m) times acceleration (a): F = m * a.

In this case, the force exerted on the scale, or the scale reading, is the force exerted by the man, which is given as 700 N. The acceleration of the elevator is 1.8 m/s^2 upwards.

To calculate the scale reading, let's break down the steps:

Step 1: Determine the net force on the man.
The net force on the man is the sum of his weight (mg) and the force caused by the acceleration (ma). The weight of the man can be calculated using the equation: weight = mass * acceleration due to gravity. The acceleration due to gravity is approximately 9.81 m/s^2.

So, the weight of the man would be: weight = mass * 9.81.

Step 2: Calculate the force exerted on the scale.
Since the scale reading shows the force exerted on it, we can use the equation: force on the scale = force on the man.

Now, let's put it all together:

Step 1:
Calculate the weight of the man:
weight = mass * 9.81.

Step 2:
Calculate the net force on the man:
net force = weight + (mass * acceleration).

Step 3:
Since the force on the scale is equal to the net force on the man, we have:
force on the scale = net force.

Using this information, you can now calculate the scale reading by using the formula:
force on the scale = 700 + (mass * 1.8).

Make sure to check your units and use the appropriate value for the acceleration due to gravity (9.81 m/s^2).

Hope this clears things up for you!