Answer:
C. chemical energy from the batteries
Explanation:
Remote-controlled car or commonly called RC cars are toy vehicles that are controlled or propelled to move from a distance by a wire-connected remote that sends radiowaves to the receiver. According to this question involving the remote-controlled car Lena is playing with, a transmitter from the remote propels the wheel and axle to make the car move.
The car contains a battery cell that uses it's chemical energy as a source of power for the wheel and axle system. Hence, the chemical energy from the batteries of a remote-controlled car powers the wheel and axle to make the car move.
The answer is amino acids :). hope that helped!
To solve this problem we will use Henry's law. This law states that at a constant temperature, the amount of gas dissolved in a liquid is directly proportional to the partial pressure exerted by that gas on the liquid. Mathematically it is formulated as follows:
Where,
= Henry's constant for C02 at 25°C is equal to 
C = Gas concentration is 0.19M
Replacing we have,
Therefore the pressure of carbon dioxide is 5.277 atm
Answer:
1. 2.67 s
2. 0.1 m/s²
Explanation:
1. Determination of the time taken for the penguin to fall.
Height (h) of cliff = 35 m
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) =?
h = ½gt²
35 = ½ × 9.8 × t²
35 = 4.9 × t²
Divide both side by 4.9
t² = 35 / 4.9
Take the square root of both side
t = √(35 / 4.9)
t = 2.67 s
Thus, it will take 2.67 s for the penguin to fall onto the head of a napping polar bear.
2. Determination of the acceleration of the penguin.
Initial velocity (u) = 0 m/s.
Final velocity (v) = 2 m/s.
Time (t) = 20 s
Acceleration (a) =?
a = (v – u)/t
a = (2 – 0)/ 20
a = 2 / 20
a = 0.1 m/s²
Thus, the acceleration of the penguin is 0.1 m/s²
Answer:
Explanation:
In the decibel scale , intensity of sound changes logarithmically as follows
Value in decibel scale , the value of I₀ = 10⁻¹² W /m².
Putting the values
W/m²
Similarly for 54 dB sound intensity can be given as follows
I = 10⁻¹² x 
W / m²
For intensity of sound the relation is as follows
I = 2π²υ²A²ρc where υ is frequency , A is amplitude , ρ is density of air and c is velocity of sound .
Putting the given values for 71 dB
= 2π² x 504²xA²x 1.21 x 346
A² = 60.03 x 10⁻¹⁶
A = 7.74 x 10⁻⁸ m
For 54 dB sound
= 2π² x 504²xA²x 1.21 x 346
A² = 1.1978 x 10⁻¹⁶
A = 1.1 x 10⁻⁸ m
