A. physical change
Look at the way water freezes and changes to ice<span>. The matter is still going to be the same. its just the physical property that changed.
<u>PHYSICAL= TEMPORARY</u>
<u>CHEMICAL= PERMANENT</u></span>
Answer:
19 N
Explanation:
From the question given above, the following data were obtained:
Pressure (P) = 1.9 kPa
Length (L) = 10 cm
Force (F) =?
Next, we shall convert 1.9 KPa to N/m². This can be obtained as follow:
1 KPa = 1000 N/m²
Therefore,
1.9 KPa = 1.9 KPa × 1000 N/m² / 1 KPa
1.9 KPa = 1900 N/m²
Thus, 1.9 KPa is equivalent to 1900 N/m².
Next, we shall convert 10 cm to m. This can be obtained as follow:
100 cm = 1 m
Therefore,
10 cm = 10 cm × 1 m / 100 cm
10 cm = 0.1 m
Thus, 10 cm is equivalent to 0.1 m
Next, we shall determine the area of the square. This can be obtained as follow:
Length (L) = 0.1 m
Area of square (A) =?
A = L²
A = 0.1²
A = 0.01 m²
Thus, the area of the square is 0.01 m².
Finally, we shall determine the force that must be exerted on the sensor in order for it to turn red. This can be obtained as follow:
Pressure (P) = 1900 N/m²
Area (A) = 0.01 m²
Force (F) =?
P = F/A
1900 = F / 0.01
Cross multiply
F = 1900 × 0.01
F = 19 N
Therefore, a force of 19 N must be exerted on the sensor in order for it to turn red.
Answer:6.298,4.1,1.9015
Explanation:
Wavelength=
=
=4.397 m
Distance of 3rd speaker from speaker A is x
From B 78-x
Difference between the distances must be a whole number of wavelengths
First
for 1 st wavelength
2x=8.2+4.397=12.597
x=6.298m
second
For zero wavelength
2x=8.2
x=4.1m
Third
x=1.9015 m
Answer:
<em>a) 0.72 V</em>
<em>b) 19.2 mA</em>
<em>c) 2.304 Watts</em>
Explanation:
A transformer is used to step-up or step-down voltage and current. It uses the principle of electromagnetic induction. When the primary coil is greater than the secondary coil, the it is a step-down transformer, and when the primary coil is less than the secondary coil, the it is a step-up transformer.
number of primary turns = 
= 500 turns
input voltage = 
= 120 V
number of secondary turns = 
= 3 turns
output voltage = 
= ?
using the equation for a transformer
substituting values, we have
= 360/500 =<em> 0.72 V</em>
<em></em>
b) by law of energy conservation,
where
= input current = ?
= output voltage = 3.2 A
= output voltage = 0.72 V
= input voltage = 120 V
substituting values, we have
120 = 3.2 x 0.72
120 = 2.304
= 2.304/120 = 0.0192 A
= <em>19.2 mA</em>
<em></em>
c) power input = 
==> 0.0192 x 120 = <em>2.304 Watts</em>
