Answer:
I think the answer is C.
Explanation:
A primary source is a first hand account of an event while a secondary source is a retelling or second hand account meaning as many details will be prevalent.
Answer:
a = F-ff/m
Explanation:
According to Newton's second law of motion which states that "the rate of change in momentum of a body is directly proportional to the applied force F and acts in the direction of the force.
Mathematically;
F = ma
Since two forces acts on the cart i.e the moving force F and the frictional force Ff , we will take the sum of the forces.
∑F = ma where
m is the mass of the cart
a is its acceleration
∑F = F+(-ff )(since frictional force is an opposing force)
F - ff = ma
Dividing both sides by mass m
a = F-ff/m
Answer:
4.2s
Explanation:
Given parameters:
Power = 2190W
Mass of box = 1.47 x 10⁴g
distance = 6.34 x 10⁴mm
Unknown:
Time = ?
Solution:
Power is the rate at which work is done;
Mathematically;
Power = 
Time = 
Work done = weight x height
convert mass to kg;
100g = 1kg;
1.47 x 10⁴g = 14.7kg
convert the height to m;
1000mm = 1m
6.34 x 10⁴mm gives 63.4m
Work done = 14.7 x 9.8 x 63.4 = 9133.4J
Time taken = 
= 4.2s
People, and cars
is the right answer!!!!!!!!!!!!!!!!!!!!!!!!!!
