Answer:
Point a
Explanation:
The potential energy of an object is given by :
P = mgh
m is mass, g is acceleration due to gravity, h is height above ground level.
Potential energy is directly proportional to the position of an object.
In the attached figure, the maximum height is shown at point (a). It means it will have maximum potential energy at a as compared to b,c and d.
 
        
             
        
        
        
PV = 400 x 0.08 = 32 J
Hope this helps
        
             
        
        
        
Answer:
Kinda? Depends what the question is fully asking
Explanation:
Acceleration is a change in velocity. So I guess if the velocity of something is -2 m/s and its positively accelerating at a value of +1 m/s, then that means every second its velocity changes by +1m/s. 
So that -2 m/s thing after one second will be going -1 m/s.
After another second it'll be going 0 m/s. 
After another itll be going +1 m/s and so on. 
So at one point for a brief moment, it can have an acceleration but be at 0 m/s velocity.
 
        
             
        
        
        
So,  If the silica cyliner of the radiant wall heater is rated at 1.5 kw its temperature when operating is 1025.3 K
To estimate the operating temperature of the radiant wall heater, we need to use the equation for power radiated by the radiant wall heater.
<h3>Power radiated by the radiant wall heater</h3>
The power radiated by the radiant wall heater is given by P = εσAT⁴ where
-  ε = emissivity = 1 (since we are not given), 
- σ = Stefan-Boltzmann constant = 6 × 10⁻⁸ W/m²-K⁴, 
- A = surface area of cylindrical wall heater = 2πrh where 
- r = radius of wall heater = 6 mm = 6 × 10⁻³ m and 
- h = length of heater = 0.6 m, and 
- T = temperature of heater
Since P = εσAT⁴
P = εσ(2πrh)T⁴
Making T subject of the formula, we have
<h3>Temperature of heater</h3>
T = ⁴√[P/εσ(2πrh)]
Since P = 1.5 kW = 1.5 × 10³ W
Substituting the values of the variables into the equation, we have
T = ⁴√[P/εσ(2πrh)]
T = ⁴√[1.5 × 10³ W/(1 × 6 × 10⁻⁸ W/m²-K⁴ × 2π × 6 × 10⁻³ m × 0.6 m)]
T = ⁴√[1.5 × 10³ W/(43.2π  × 10⁻¹¹ W/K⁴)]
T = ⁴√[1.5 × 10³ W/135.72  × 10⁻¹¹ W/K⁴)]
T = ⁴√[0.01105 × 10¹⁴ K⁴)]
T = ⁴√[1.105 × 10¹² K⁴)]
T = 1.0253 × 10³ K
T = 1025.3 K
So, If the silica cylinder of the radiant wall heater is rated at 1.5 kw its temperature when operating is 1025.3 K
Learn more about temperature of radiant wall heater here:
brainly.com/question/14548124
 
        
             
        
        
        
Answer:
1. It undergoes reflection. 2. It undergoes refraction. 3. It undergoes diffraction.
Explanation:
1. It undergoes reflection. This is because it bounces off surfaces when incident on them.
2. It undergoes refraction. This is because it changes direction when it passes from one medium to another
3. It undergoes diffraction. This is because it spreads out when it passes through doors and windows similar in dimension to the dimensions of its wavelength