Answer: Reliable and trusted
 
        
                    
             
        
        
        
Answer:
Explanation:
mass, m = 1 kg 
Position (2, 3 ) m
height, h = 2 m 
acceleration due to gravity, g = 9.8 m/s^2 
Here, no force is acting in horizontal direction, the force of gravity is acting in vertical direction, so the work done by the gravitational force is to be calculated. 
Force  mass x acceleration due to gravity 
F = 1 x 9.8 = 9.8 N 
Work = force x displacement x CosФ
Where, Ф be the angle between force vector and the displacement vector. 
Here the value of Ф is 180° as the force acting vertically downward and the displacement is upward 
So, W = 9.8 x 2 x Cos 180°
W = - 19.6 J
Thus, option (A) is correct. 
 
        
             
        
        
        
The cost of boiling 500 cm³ of water using the 3 KW Kettle is 1.35p
<h3>What is power? </h3>
This is defined as the rate in which energy is consumed. Electrical power is expressed mathematically as:
Power (P) = Energy (E) / time (t)
P = E / t
<h3>How to determine the energy</h3>
- Power (P) = 3 KW
- Time (t) = 3 mins = 3 / 60 = 0.05 h
- Energy (E) =?
E = Pt
E = 3 × 0.05
E = 0.15 KWh
<h3>How to determine the cost</h3>
- Energy (E) = 0.15 KWh
- Cost per unit = 9p
- Cost =?
Cost = Energy × cost per unit
Cost = 0.15 × 9 
Cost = 1.35p
Learn more about electrical power:
brainly.com/question/64224
#SPJ1
 
        
             
        
        
        
The magnitude of velocity for this car is equal to 1.5 m/s.
<u>Given the following data:</u>
- Momentum of car = 3,000 kgm/s.
To calculate the magnitude of velocity for this car:
<h3>What is momentum?</h3>
In Science, momentum simply means a multiplication of the mass of an object and its velocity. 
Mathematically, momentum is giving by the formula;

Making velocity the subject of formula, we have:

Substituting the given parameters into the formula, we have;

Velocity = 1.5 m/s.
Read more on momentum here: brainly.com/question/15517471
 
        
             
        
        
        
The sunlight of all colors passes through air, the blue part causes charged particles to oscillate faster than does the red part. More of the sunlight entering the atmosphere is blue than violet, however, and our eyes are somewhat more sensitive to blue light than to violet light, so the sky appears blue.