Which factor makes the biggest difference when studying the effects of radiation on an organism?(1 point)
Responses
the number of cells exposed to the radiation
the number of cells exposed to the radiation
the duration of exposure
the duration of exposure
the frequency of the radiation
the frequency of the radiation
the size of the organism
the number of cells exposed to the radiation
why is that the correct answer?
The number of cells exposed to radiation makes the biggest difference when studying the effects of radiation on an organism because the more cells that are exposed, the greater the potential damage that can occur. Radiation can cause mutations, cell death, and other harmful effects when it interacts with cells, so the more cells that are exposed, the higher the likelihood of negative effects occurring. The number of cells exposed directly affects the extent of damage that can occur in the organism as a whole.
How much more kinetic energy does a 6-kilogram bowling ball have when it is rolling at 16 mph (7.1 meters per second) than when it is rolling at 14 mph (6.2 meters per second)?
KE=12mv2
(1 point)
Responses
35.9 J
35.9 J
151.2 J
151.2 J
1.3 J
1.3 J
266.5 J
To find the kinetic energy of the bowling ball at each speed, we can use the kinetic energy formula KE = 0.5 * m * v^2, where m is the mass of the bowling ball and v is its speed in meters per second.
For the first speed of 6.2 m/s:
KE = 0.5 * 6 * (6.2)^2
KE = 0.5 * 6 * 38.44
KE ≈ 115.3 J
For the second speed of 7.1 m/s:
KE = 0.5 * 6 * (7.1)^2
KE = 0.5 * 6 * 50.41
KE ≈ 150.8 J
The kinetic energy difference between the two speeds is:
150.8 J - 115.3 J ≈ 35.5 J
So, the closest option is:
35.9 J
Therefore, the answer is 35.9 J.
A bar magnet is held in place while another bar magnet is placed near it. The second bar magnet spins around and attaches to the first magnet on one end. Which statement is correct about the energy stored in the magnetic field? (1 point)
Responses
The decrease in the energy stored in the system is proportional to the decrease in kinetic energy.
The decrease in the energy stored in the system is proportional to the decrease in kinetic energy.
The increase in the energy stored in the system is proportional to the increase in kinetic energy.
The increase in the energy stored in the system is proportional to the increase in kinetic energy.
The decrease in the energy stored in the system is proportional to the increase in kinetic energy.
The decrease in the energy stored in the system is proportional to the increase in kinetic energy.
The increase in the energy stored in the system is proportional to the decrease in kinetic energy.
The decrease in the energy stored in the system is proportional to the increase in kinetic energy.
When the second bar magnet spins around and attaches to the first magnet, there is a decrease in the stored magnetic energy as the two bar magnets align and create a lower energy state. This decrease in magnetic potential energy is converted into an increase in kinetic energy as the second bar magnet moves and spins around towards the first magnet. So, the decrease in energy stored in the magnetic field is proportional to the increase in kinetic energy.
Therefore, the correct statement is "The decrease in the energy stored in the system is proportional to the increase in kinetic energy."
What is the relationship between heat and thermal conductors?(1 point)
Responses
Thermal conductors facilitate heat, the transfer of thermal energy.
Thermal conductors facilitate heat, the transfer of thermal energy.
Thermal conductors impede heat, the transfer of thermal energy.
Thermal conductors impede heat, the transfer of thermal energy.
Thermal conductors allow all of the thermal energy in one object or substance to be easily transferred to another object or substance.
Thermal conductors allow all of the thermal energy in one object or substance to be easily transferred to another object or substance.
Thermal conductors have no effect on heat.
Thermal conductors facilitate heat, the transfer of thermal energy.
Thermal conductors are materials that allow heat to flow through them easily, facilitating the transfer of thermal energy from one object to another. This means that thermal conductors help in the conduction of heat, making them efficient at transferring thermal energy.
Which scenario shows radiation?(1 point)
Responses
Eggs cook in a skillet.
Eggs cook in a skillet.
Air warmed by a floor radiator rises to the top of a room, forcing cooler air downward.
Air warmed by a floor radiator rises to the top of a room, forcing cooler air downward.
Eggs boil in a pot of water.
Eggs boil in a pot of water.
The air under a reading lamp is warmed.