Answer:19ohms
Explanation:
equivalent resistance=5+2+12
equivalent resistance=19ohms
Answer:
B. decreases while his angular speed remains unchanged.
Explanation:
His angular speed will always be the same as the wheel's angular speed, which remains constant as it's in uniform motion. As for linear speed, which is defined as the product of angular speed and distance r to the center of rotation, and his distance to center is decreasing, his linear speed must be decreasing as well.
Answer:
12 nC
Explanation:
Capacity of the parallel plate capacitor
C = ε₀ A/d
ε₀ is constant having value of 8.85 x 10⁻¹² , A area of plate , d is distance between plate
Area of plate = π r²
= 3.14 x (0.8x 10⁻²)²
= 2 x 10⁻⁴
C = ( 8.85 X 10⁻¹² x 2 x 10⁻⁴ ) / 2.8 x 10⁻³
= 7.08 x 10⁻¹³
Potential difference between plate = field strength x distance between plate
= 6 x 10⁶ x 2.8 x 10⁻³
= 16.8 x 10³ V
Charge on plate = CV
=7.08 x 10⁻¹³ X 16.8 X 10³
11.9 X 10⁻⁹ C
12 nC .
So, option 3 or the ambulance sound waves have more waves and shorter wavelength is the correct reason for ambulance siren having higher pitch compared to fire truck siren
Explanation:
Pitch of any sound wave is determined as the clarity in frequency of notes or the number of times a cycle is repeated for a single second. So pitch is similar to frequency. And frequency is the measure of number of complete cycles in a second. So if the ambulance siren has higher pitch compared to siren of fire truck. Then this means the frequency of ambulance siren is greater than the fire truck siren. As the frequency is more, then from the given options, choice 3 is correct. The ambulance siren have more waves and shorter wavelength. As more the frequency or number of waves, lesser or shorter is the wavelength of sound wave from ambulance.
The mass of ice melted as a result of friction between the ice and the horizontal surface is 2.78g
<u>Explanation:</u>
Given,
Temperature, T = 0°C
Initial mass, Mi = 62kg
Speed, s = 5.48m/s
Distance, x = 26.8m
Friction is present.
Mass of ice melted = ?
We know,
The amount of energy required for the melting of ice is exactly equal to the initial kinetic energy of the block of ice
and
Therefore, 
KE = 930.94 Joules
Ice melting lateral heat is 334 kJ/kg = 334000 J/kg.
Therefore, the melted mass of the ice = 930.94 / 334000 = 0.00278 kg = 2.78 g.
Thus, The mass of ice melted as a result of friction between the ice and the horizontal surface is 2.78g
