2.1 Motor met 'n gewig van 10 000 N ry ooswaarts op 'n gelyke pad, terwyl die enjin 'n krag, F, ooswaarts toepas - NSC Technical Sciences - Question 2 - 2022 - Paper 1

Newton's Second Law states that the acceleration of an object is directly proportional to the net force acting upon the object and inversely proportional to its mass. This can be mathematically represented as:

$F_{net} = ma$

where ( F_{net} ) is the net force, ( m ) is the mass, and ( a ) is the acceleration.

To calculate the acceleration of the canoe, use Newton's Second Law:

$F_{net} = ma\Rightarrow a = \frac{F_{net}}{m}$

Given that the net force is ( 80 N ) (assuming forward direction) and mass is ( 5 kg ), we find:

• The force acting on the canoe is ( 50 N ) (applied pull) minus resistive forces ( 2 N ) (friction and drag), giving a net force of ( 48 N ).

Now: $a = \frac{48N}{5kg} = 9.6 m/s²$

We need to find the resulting force required to accelerate the canoe from (3, m/s) to (5, m/s) over (6, seconds). First, calculate the acceleration:

$a = \frac{(5 m/s - 3 m/s)}{6 s} = \frac{2 m/s}{6 s} = 0.333 m/s²$

Next, using Newton’s Second Law:

$F = ma = (mass)(acceleration) \Rightarrow \text{mass of canoe is assumed as } 5 kg.\Rightarrow F = 5 kg \times 0.333 m/s² = 1.665 N$

Hence, a net force of (1.665 N) will be required.

Newton's First Law states that an object will remain at rest or continue moving in a straight line unless acted upon by a non-zero resultant net force. This implies that an object maintains its current state of motion if no force is applied.

To determine the tension ( T ) in the chain using a scale method, first draw a scale diagram based on the forces acting on the engine:

• Represent the weight ( w = 8 500 N ) vertically downward.
• Draw the tension ( T ) at an angle of 29.2° from the vertical.
• Use the scale: 1 mm = 50 N and calculate the resultant forces accordingly on graph paper.

To find the mass of the engine, use the formula for gravitational weight:

$w = mg \Rightarrow m = \frac{w}{g}$

Substituting in the given weight of the engine:

$m = \frac{8 500 N}{9.81 m/s²} \approx 866.5 kg$

Thus, the mass of the engine is approximately ( 866.5 kg ).