Special Relativity Answers

12 verified answers2 views
1
Free Preview

Frank stands still while throwing a dart toward a target with a speed of 25 m/s.

A
The speed is 25 m/s for both people.
B
The speed is greater than 25 m/s for Frank only.
C
The speed is greater than 25 m/s for the observer only.
D
The speed is less than 25 m/s for both people.
2
Free Preview

Time is a phenomenon in which objects in motion and objects at rest experience time differently.

Answer not available
3

Maria listed four important points about Einstein’s special theory of relativity.1) applies to any object moving more slowly than the speed of light2) applies to objects moving in a straight path3) describes the relationship between time and space4) applies to uniformly moving objects

A
Change the first point to “applies to objects moving almost at the speed of light.”
B
For point 2, include objects moving in a curved path.
C
For point 3, replace the word “space” with the word “motion.”
D
Change the fourth point to “applies to accelerating objects.”
6

Alyssa is carrying a water balloon while running down a field at a speed of 14 m/s. She tosses the water balloon forward toward a bucket with a speed of 23 m/s. Alyssa’s friend Naya is standing still next to the field.

A
The speed of the balloon is 23 m/s for Alyssa and 14 m/s for Naya.
B
The speed of the balloon is 37 m/s for Alyssa and 23 m/s for Naya.
C
The speed of the balloon is 14 m/s for Alyssa and 23 m/s for Naya.
D
The speed of the balloon is 23 m/s for Alyssa and 37 m/s for Naya.
7

Alex is standing still and throws a football with a speed of 10 m/s to his friend, who is also standing still. The two friends are standing 5 meters apart.

A
Alex observes it as 10 m/s, and his friend observes it as less than 10 m/s.
B
Alex observes it as less than 10 m/s, and his friend observes it as 10 m/s.
C
Both Alex and his friend observe it as 10 m/s.
D
Both Alex and his friend observe it as less than 10 m/s.
8

According to the concept of length contraction, what happens to the length of an object as it approaches the speed of light and then slows down, eventually coming to a stop?

A
It is always observed as contracting.
B
It is always observed as the same length.
C
It is observed as expanding and then contracting back to its original length.
D
It is observed as contracting and then expanding back to its original length.
9

Basim’s robotics team builds a robot that travels at 9 m/s and can fire a tennis ball at a target.

A
The robot fires the ball forward with a speed of 7 m/s.
B
The robot fires the ball backward with a speed of 7 m/s.
C
The robot fires the ball backward with a speed of 2 m/s.
D
The robot fires the ball forward with a speed of 2 m/s.
10

Yanni is sitting in the stands watching a football game. The quarterback runs forward toward the end zone and throws a pass straight downfield to a player for a touchdown. The quarterback ran at a speed of 8 m/s and threw the ball with a speed of 15 m/s.

A
For Yanni, the speed of the ball is 23 m/s, and for the quarterback, the speed of the ball is 15 m/s.
B
For Yanni, the speed of the ball is 15 m/s, and for the quarterback, the speed of the ball is 8 m/s.
C
For both Yanni and the quarterback, the speed of the ball is 23 m/s.
D
For both Yanni and the quarterback, the speed of the ball is 15 m/s.
11

Basim’s robotics team builds a robot that travels at 9 m/s and can fire a tennis ball at a target.

A
The robot fires the ball forward with a speed of 7 m/s.
B
The robot fires the ball backward with a speed of 7 m/s.
C
The robot fires the ball backward with a speed of 2 m/s.
D
The robot fires the ball forward with a speed of 2 m/s.
13

In an action movie, a spy is lying still on top of a train. The train is moving at a speed of 95 km/h. Three bad guys are after the spy. One is in a helicopter flying above the train and moving at the same speed in the same direction as the train. The second is a spotter sitting above a tunnel opening that the train is headed for. The third is in a car that is driving alongside the train, in the opposite direction, at a speed of 105 km/h.

A
The person in the car and the spotter above the tunnel will both observe the speed of the person on the train as 95 km/h.
B
The person in the helicopter and the spotter above the tunnel will both observe the speed of the person on the train as 95 km/h.
C
The spotter above the tunnel will observe the speed of the spy as 95 km/h, and the person in the car will observe the speed of the spy as 200 km/h.
D
The person in the helicopter will observe the speed of the spy as 95 km/h, and the person in the car will observe the speed of the spy as 105 km/h.
14

Jin is standing still and watching an archer on a horse traveling away from a target. The archer is moving at a speed of 4 m/s and shoots the arrow toward the target with a speed of 17 m/s.

A
For Jin, the speed of the arrow is 21 m/s, and for the archer, the speed of the arrow is 4 m/s.
B
For Jin, the speed of the arrow is 13 m/s, and for the archer, the speed of the arrow is 17 m/s.
C
For both Jin and the archer, the speed of the arrow is 21 m/s.
D
For both Jin and the archer, the speed of the arrow is 17 m/s.
15

Which describes time dilation?

A
The faster an object moves, the more stretched time becomes.
B
The more slowly an object moves, the more stretched time becomes.
C
The faster an object moves, the more time it takes for light to travel a given distance.
D
The faster an object moves, the less time it takes for light to travel a given distance.

Did you find these answers helpful?