The Ray Approximation - Questions

Definition of rays
The approximation
Shadows

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be
(A) vertical surfaces oriented north-south.
(B) vertical lines.
(C) horizontal east-west lines.
(D) horizontal north-south lines.

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be
(A) vertical surfaces oriented north-south.
No. --- That describes the wavefronts.

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be
(B) vertical lines. --- No.
Those would not be perpendicular to the wavefronts.

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be
(C) horizontal east-west lines.
Yes. --- Pointing away from the sun.

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be
(D) horizontal north-south lines.
No. --- Those would not be perpendicular to the wavefronts.

All of the following statements are true. Which one states the ray approximation?
(A) Rays are perpendicular to wavefronts.
(B) Rays spread outward from a source.
(C) For short wavelengths, rays are straight lines.
(D) For long wavelengths, rays bend around corners.

All of the following statements are true. Which one states the ray approximation?
(A) Rays are perpendicular to wavefronts.
No. --- That is the definition of a ray.

All of the following statements are true. Which one states the ray approximation?
(B) Rays spread outward from a source.
No. --- That always happens.

All of the following statements are true. Which one states the ray approximation?
(C) For short wavelengths, rays are straight lines.
Yes. --- approximately.

All of the following statements are true. Which one states the ray approximation?
(D) For long wavelengths, rays bend around corners.
No. --- True but not the ray approximation.

The part of a shadow where no light rays go is called the
(A) inner shadow.
(B) umbra.
(C) penumbra.
(D) zone of totality.

The part of a shadow where no light rays go is called the
(A) inner shadow. --- No.
Although that would make sense.

The part of a shadow where no light rays go is called the
(B) umbra. --- Yes.
The darkest part of the shadow.

The part of a shadow where no light rays go is called the
(C) penumbra. --- No.
That is where some but not all of the rays are blocked.

The part of a shadow where no light rays go is called the
(D) zone of totality. --- No.
That only applies to eclipses.

The Ray Approximation - Questions Definition of rays The approximation Shadows

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be (A) vertical surfaces oriented north-south. (B) vertical lines. (C) horizontal east-west lines. (D) horizontal north-south lines.

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be (A) vertical surfaces oriented north-south. No. --- That describes the wavefronts.

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be (B) vertical lines. --- No. Those would not be perpendicular to the wavefronts.

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be (C) horizontal east-west lines. Yes. --- Pointing away from the sun.

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be (D) horizontal north-south lines. No. --- Those would not be perpendicular to the wavefronts.

All of the following statements are true. Which one states the ray approximation? (A) Rays are perpendicular to wavefronts. (B) Rays spread outward from a source. (C) For short wavelengths, rays are straight lines. (D) For long wavelengths, rays bend around corners.

All of the following statements are true. Which one states the ray approximation? (A) Rays are perpendicular to wavefronts. No. --- That is the definition of a ray.

All of the following statements are true. Which one states the ray approximation? (B) Rays spread outward from a source. No. --- That always happens.

All of the following statements are true. Which one states the ray approximation? (C) For short wavelengths, rays are straight lines. Yes. --- approximately.

All of the following statements are true. Which one states the ray approximation? (D) For long wavelengths, rays bend around corners. No. --- True but not the ray approximation.

The part of a shadow where no light rays go is called the (A) inner shadow. (B) umbra. (C) penumbra. (D) zone of totality.

The part of a shadow where no light rays go is called the (A) inner shadow. --- No. Although that would make sense.

The part of a shadow where no light rays go is called the (B) umbra. --- Yes. The darkest part of the shadow.

The part of a shadow where no light rays go is called the (C) penumbra. --- No. That is where some but not all of the rays are blocked.

The part of a shadow where no light rays go is called the (D) zone of totality. --- No. That only applies to eclipses.

The Ray Approximation - Questions

Definition of rays
The approximation
Shadows

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be
(A) vertical surfaces oriented north-south.
(B) vertical lines.
(C) horizontal east-west lines.
(D) horizontal north-south lines.

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be
(A) vertical surfaces oriented north-south.
No. --- That describes the wavefronts.

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be
(B) vertical lines. --- No.
Those would not be perpendicular to the wavefronts.

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be
(C) horizontal east-west lines.
Yes. --- Pointing away from the sun.

Suppose that the sun is setting in the west. The rays of light from the sun appear locally to be
(D) horizontal north-south lines.
No. --- Those would not be perpendicular to the wavefronts.

All of the following statements are true. Which one states the ray approximation?
(A) Rays are perpendicular to wavefronts.
(B) Rays spread outward from a source.
(C) For short wavelengths, rays are straight lines.
(D) For long wavelengths, rays bend around corners.

All of the following statements are true. Which one states the ray approximation?
(A) Rays are perpendicular to wavefronts.
No. --- That is the definition of a ray.

All of the following statements are true. Which one states the ray approximation?
(B) Rays spread outward from a source.
No. --- That always happens.

All of the following statements are true. Which one states the ray approximation?
(C) For short wavelengths, rays are straight lines.
Yes. --- approximately.

All of the following statements are true. Which one states the ray approximation?
(D) For long wavelengths, rays bend around corners.
No. --- True but not the ray approximation.

The part of a shadow where no light rays go is called the
(A) inner shadow.
(B) umbra.
(C) penumbra.
(D) zone of totality.

The part of a shadow where no light rays go is called the
(A) inner shadow. --- No.
Although that would make sense.

The part of a shadow where no light rays go is called the
(B) umbra. --- Yes.
The darkest part of the shadow.

The part of a shadow where no light rays go is called the
(C) penumbra. --- No.
That is where some but not all of the rays are blocked.

The part of a shadow where no light rays go is called the
(D) zone of totality. --- No.
That only applies to eclipses.