Take east to be the positive direction. Then the resultant force from adding <em>F</em>₁ and <em>F</em>₂ is
<em>F</em>₁ + <em>F</em>₂ = (-45 N) + 63 N = 18 N
which is positive, so it's directed east.
To this we add a third force <em>F</em>₃ such that the resultant is 12 N pointing west, making it negative, so that
18 N + <em>F</em>₃ = -12 N
<em>F</em>₃ = -30 N
So <em>F</em>₃ has a magnitude of 30 N and points west.
If the net force on a block is zero, the block will move at constant velocity
Explanation:
We can answer this question by applying Newton's second law of motion, which states that the net force on an object is equal to the product between its mass and its acceleration:
(1)
where
is the net force on the object
m is its mass
a is its acceleration
In this problem, we have a block, and the net force on it is zero:
According to eq.(1), this also implies that
So, the acceleration of the block is zero.
However, acceleration is the rate of change of velocity of a body:
where 
is the change in velocity in a time of 
. Since the acceleration is zero, this means that 
, and therefore the velocity of the object is constant.
Learn more about Newton's second law:
brainly.com/question/3820012
#LearnwithBrainly
<span>Question: How much power does an electric device use if the current is 36.0 amps and the resistance is 3.9 ohms? </span>
How?:
Equation: P = I^2 R
Meanings:
P = Power in Watts
I = Current in Ampere
R = Resistance in ohms.
Plugged in: P = 36^2<span> x 3.9 = 5054.4
Answer: P= </span>5100 watts.
HOPE THIS HELPS! ^_^
<span> </span>
Answer:
kinetic energy = 1 / 2 mv²
kinetic energy = 1 / 2 × 20 × 10 ²
kinetic energy = 1000 joules
.........
