Students build four electromagnets and test them by picking up metal tacks. Here are their partial results. 12 coils 4 tacks 24 coils 9 tacks 36 coils 13 tacks 48 coils ? tacks Which is the best prediction for the number of nails the electromagnet with 48 coils will pick up?(1 point) Responses 12 tacks 12 tacks 16 tacks 16 tacks 20 tacks 20 tacks 13 tacks
9 answers
20 tacks
How do electromagnets cause a maglev train to levitate above the track? (1 point) Responses Magnets in the track and magnets in the bottom of the train attract each other. Magnets in the track and magnets in the bottom of the train attract each other. Magnets in the track and magnets in the bottom of the train repel each other. Magnets in the track and magnets in the bottom of the train repel each other. Batteries provide electric energy to the electromagnets in the train. Batteries provide electric energy to the electromagnets in the train. Magnets in the sides of the tracks constantly repel and attract magnets in the sides of the train.
Magnets in the track and magnets in the bottom of the train repel each other.
Use the ray diagram for a lens to answer the question. Which of these best describes the type of lens shown in the ray diagram? (1 point) Responses It shows a concave lens. For this type of lens, the image position depends on the object's position relative to the focus point. It shows a concave lens. For this type of lens, the image position depends on the object's position relative to the focus point. It shows a convex lens. For this type of lens, the image position depends on the object's position relative to the focus point. It shows a convex lens. For this type of lens, the image position depends on the object's position relative to the focus point. It shows a convex lens. For this type of lens, the image is always on the opposite side of the lens as the original object. It shows a convex lens. For this type of lens, the image is always on the opposite side of the lens as the original object. It shows a concave lens. For this type of lens, the image is always on the opposite side of the lens as the original object
It shows a convex lens. For this type of lens, the image position depends on the object's position relative to the focus point.
What happens to sound waves from an object as it moves toward you?(1 point) Responses The pitch gets lower because of an increase in wavelength. The pitch gets lower because of an increase in wavelength. The pitch gets higher because of an increase in frequency. The pitch gets higher because of an increase in frequency. The pitch gets lower because of an increase in frequency. The pitch gets lower because of an increase in frequency. The pitch gets higher because of an increase in wavelength.
The pitch gets higher because of an increase in frequency.
Which combination of frequencies would produce the lowest beat frequency?(1 point) Responses 10 Hz and 15 Hz 10 Hz and 15 Hz 10 Hz and 20 Hz 10 Hz and 20 Hz 500 Hz and 600 Hz 500 Hz and 600 Hz 500 Hz and 501 Hz 500 Hz and 501 Hz
10 Hz and 20 Hz
9 answers