Explanation:
Sun— Nuclear energy is converted to heat and light energy
Corn absorbs sunlight in order to produce sugars and oxygen for plant growth.
Corn is fermented to produce ethanol, which is burned to power generators to give an electrical current The speaker takes the electrical current and produces sound.
Answer:
C.
Explanation:
A person pushing a couch will face resistive force of friction . When resistive force is greater then his force of effort , couch will not move. This force is static friction because the couch is stationary. When the force of effort is increased , magnitude of static friction also increases keeping the couch stationary. The ability of the static friction to increase its magnitude is limited by a maximum value beyond which the couch starts moving. The static friction is then converted into kinetic friction.
In rest of the three cases object is already moving so kinetic friction is in action.
Answer:
The total mechanical energy of a pendulum is conserved neglecting the friction.
Explanation:
- When a simple pendulum swings back and forth, it has some energy associated with its motion.
- The total energy of a simple pendulum in harmonic motion at any instant of time is equal to the sum of the potential and kinetic energy.
- The potential energy of the simple pendulum is given by P.E = mgh
- The kinetic energy of the simple pendulum is given by, K.E = 1/2mv²
- When the pendulum swings to one end, its velocity equals zero temporarily where the potential energy becomes maximum.
- When the pendulum reaches the vertical line, its velocity and kinetic energy become maximum.
- Hence, the total mechanical energy of a pendulum as it swings back and forth is conserved neglecting the resistance.
Answer:
Let d be the density of the water (1000 kg / m^3 eq to 1 gm / cm^3)
P = d g h for the pressure due to a column at the bottom of the column.
P = 1000 kg / m^3 * 10 m/s^2 * 10 m = 10^5 kg / m * s^2 = 10^5 N/m
