Question

1. fill in the empty a rightward force of 125 n is applied to a 18 kg object to accelerate it to the right. a friction force between the object and the surface is 42 n. $f_{norm} = $ $= f_{frict}$ $f_{app} = $ $f_{grav} = $ units force: n mass: kg accel/n: m/s/s $m = $ $a = $ $f_{net} = $

Explanation:

Step1: Identify given applied force

$F_{app} = 125\ \text{N}$

Step2: Identify given friction force

$F_{frict} = 42\ \text{N}$

Step3: Calculate gravitational force

$F_{grav} = m \cdot g = 18\ \text{kg} \cdot 9.8\ \text{m/s}^2 = 176.4\ \text{N}$

Step4: Determine normal force

Since vertical forces balance, $F_{norm} = F_{grav} = 176.4\ \text{N}$

Step5: Identify given mass

$m = 18\ \text{kg}$

Step6: Calculate net horizontal force

$F_{net} = F_{app} - F_{frict} = 125\ \text{N} - 42\ \text{N} = 83\ \text{N}$

Step7: Calculate acceleration

$a = \frac{F_{net}}{m} = \frac{83\ \text{N}}{18\ \text{kg}} \approx 4.61\ \text{m/s}^2$

Answer:

$F_{norm} = 176.4\ \text{N}$
$F_{frict} = 42\ \text{N}$
$F_{app} = 125\ \text{N}$
$F_{grav} = 176.4\ \text{N}$
$m = 18\ \text{kg}$
$F_{net} = 83\ \text{N}$
$a \approx 4.61\ \text{m/s}^2$