Answer:
A. The athlete isn’t doing any work because he doesn’t move the weight.
Explanation:
We must remember the definition of work, which says that work is equal to the product of mass by the distance displaced. In this case, the athlete only does work when he lifts the weight from the ground to the point where he holds the weight suspended.
So when he's holding the weight, he doesn't do any work.
Answer: True.
Explanation:
You would be able to visualize the basketballs height going up and when it sinks down into the hoop.
Galileo Galilei is one of the key figures in the history of Science, being the first to apply the experimental-mathematical scientific method. He carried out experiments and careful observations in kinematics (his studies on the trajectory of projectiles are famous) and dynamics (it should be noted his careful experiments with inclined planes), establishing the first law of Dynamics (which Newton will later collect and refine in his Principles); and in Astronomy, with which he could unequivocally support the heliocentric theory.
His experiments were addressed by methodologies that allowed him to precisely find his mathematical calculations and to verify theories he was developing over time. His manuscripts were key to disseminate the applied method and extrapolate them to other scientific areas.
Therefore the correct answer is C.
Answer:
5.5g of ice melts when a 50g chunk of iron at 80°C is dropped into a cavity
Explanation:
The concept to solve this problem is given by Energy Transferred, the equation is given by,
Where,
Q= Energy transferred
m = mass of water
c = specific heat capacity
Temperature change (K or °C)
Replacing the values where mass is 50g and temperature is 80°C to 0°C we have,
Then we can calculate the heat absorbed by m grams of ice at 0°C, then
How Q_1=Q_2, so
Then 5.5g of ice melts when a 50g chunk of iron at 80°C is dropped into a cavity
Answer:
(A) FM Radio had a somewhat shorter ranger than AM radio, but better sound quality.
Explanation:
FM Radio was invented in 1933 by Edwin Armstrong who was an American engineer. FM stands for frequency modulation and AM stands for Amplitude Modulation.
FM is used for most broadcasts of music and FM radio stations use a very high-frequency range of radio frequencies.
In FM Radio, the sound is transmitted through changes in frequency. Both FM and AM radio signals experience frequent change in amplitude, they are far less noticeable on FM.
When switching between stations, FM antenna is alternating between different frequencies, and not amplitudes and this produces a much clearer sound and allows for smoother transitions with little to no audible static.
FM signals can be interfered by barriers and this could affect the signal strength. FM Radio signals are more clearer in a mountainous area that has no barrier.
AM radio was able to carry signals farther than AM radio.
