Answer: 2.7m/s
Explanation:
cyclist fight only against the component of weight along the road (no friction) , that is:
fx =Wsin6° = mgsin6°=68*9.8*sin6°=69.6N downward
so the force that moves the bike over the hill will be equal to fx but upward
Now we now that the power P = 0.25hp= 186.5W is:
P=f*v so v = P/fx = 186.5/69.6 = 2.7m/s
Answer:
400 Watts
Explanation:
The main function of a voltage transformer is to change alternating current (ac) voltage from one voltage level to another. The relationship between the primary coil and secondary coil of a transformer is a function of ratio of the voltage or current and number of turns or loop. The ratio of the voltages between the two coils is equal to the ratio of number of loops in the two coils.

Varying the number of winding in the primary and secondary coils allows the transformer to step-up or step-down voltages while power is neither increased nor decreased in the primary or secondary except for some minor losses such as iron losses, copper losses, hysteresis losses, eddy current losses, stray loss, and dielectric losses. Therefore, the power in the primary and secondary are the same. The power supplied to the 20-ohm resistor terminal in the secondary coil will be 400 Watts.
The given statement"If the pressure of a gas sample is quadrupled and the absolute temperature is doubled" is false.
Answer: Option B
<u>Explanation:</u>
As we know the direct relationship between Pressure and Temperature by the Gay-Lussac’s Law,

From this, we get,


So, according to given statement, we have 
Then from the above expression, we can find out the value of
when pressure increased by 4 times of initial pressure as,

Hence, we get,

Hence, from the above expression we can say that as we increase the pressure four times, the temperature does not get doubled. So, the given statement in the question is false.
The answer is B) A honeybee does a dance to tell the other bees where to find flowers.
Honeybees do not dance, first of all.
Second, that is not an adaptation. That is more like a message. An adaptation is changing to the environment to survive. This is not changing to the environment. They are just signaling the other bees.
A, C, and D are all adaptations. They change so that they can survive. They do a different method than usual.
~Deceptiøn
Answer:
a) The potential energy in the system is greatest at X.
Explanation:
Let be X the point where a ball rests at the top of a hill. By applying the Principle of Energy Conservation, the total energy in the physical system remains constant and gravitational potential energy at the top of the hill is equal to the sum of kinetic energy, a lower gravitational energy and dissipated work due to nonconservative forces (friction, dragging).

Conclusions are showed as follows:
a) The potential energy in the system is greatest at X.
b) The kinetic energy is the lowest at X and Z.
c) Total energy remains constant as the ball moves from X to Y.
Hence, the correct answer is A.