Answer:
Explanation:
mass of coffee filter, m = 1.4 h
height, h = 4 m
velocity, v = 0.5 m/s
The energy conservation
Potential energy of filter = kinetic energy of filter + energy gained by the air molecules
m x g x h = 0.5 x mv² + energy gained by the air molecules
0.0014 x 9.8 x 4 = 0.5 x 0.0014 x 0.5 x 0.5 + Energy gained by the air molecules
Energy gained by the air molecules = 0.05488 - 0.00000175
= 0.054878 J
If the 30 N on the rope were pulled straight up, it would offset the force of gravity ( m g = 10 kg * 9.8 N/kg = 98 N) , leaving a net force up from the ground on the sled of 98-30 = 68 N. Since the rope is pulled at the angle of 25o, only part of the force is in the upward direction, (30N)(sin(25) = (30)(.423) = 12.7. So the net force becomes 98 N down offset by 12.7 up or 98-12.7 = 85.3 N. Ah, there it is: C.
Answer:
Explanation:
The bulbs becomes dimmer because effective resistance of the circuit increases since the resistance of the circuit in series connection involves adding the individual resistance compared to in parallel connection where the effective resistance = 1 / R1 + 1/R2 = R1 R2 / ( R2 + R1). The brightness remains the same because the lightbulbs must be of the same resistance. Also using ohm's law
V = IR
I = V / R
I is inversely proportional to the current in the circuit so as R, effective resistance of the circuit increases, I, current decreases and vice versa
Answer:
All magnets have north and south poles. Opposite poles are attracted to each other, while the same poles repel each other. When you rub a piece of iron along a magnet, the north-seeking poles of the atoms in the iron line up in the same direction. The force generated by the aligned atoms creates a magnetic field.
Explanation: