**Unit 3: Motion in Two
Dimensions**

**Problem Set B**

The following selection of problems are sample problems. Individual student problem sets will vary since numerical information is randomly-generated.

**Directions:**

For the following problems:

- Compute the unknown quantity and enter the answer in the blank.
- Unless told otherwise, enter positive numbers for your answers.
- Do not round any computed numbers until the last calculation.
- Enter your answers accurate to the second decimal place (unless told otherwise).

**Problem 1:**

A river flows due east at 2.4 m/s. A boat crosses the river from the south shore to the north shore by maintaining a constant velocity of 7.2 m/s due north relative to shore. What is the magnitude of the velocity of the boat (in m/s) relative to the shore?

**Problem 2:**

(Referring to the previous problem.) If the river is 239 m wide and the boat heads directly across it, then how much time (in seconds) does it take the boat to reach the opposite shore?

**Problem 3:**

(Referring to the previous problem.) If the river is 239 m wide and the boat heads directly across it, then how far downstream (in meters) has the boat moved by the time it reaches the North shore?

**Problem 4:**

A boat heads due east directly across a 116-m wide river. The water flows due south with a speed of 2.1 m/s with respect to the shore. The boat speed with respect to the water is 2.8 m/s. Determine the magnitude of the velocity (in m/s) with respect to the shore.

**Problem 5:**

(Referring to the previous problem.) Determine the direction (in degrees) of the velocity with respect to the shore. Use the counter-clockwise from east convention.

**Problem 6:**

(Referring to the previous problem.) Determine the distance (in m) that the boat will have traveled downstream when it has reached the opposite shore.

**Problem 7:**

The pilot of an aircraft (flying at some angle) wishes to fly due west in a wind blowing at 44 km/h toward the south. If the speed of the aircraft in the absence of wind is 163 km/h, in what direction (in degrees) should the aircraft head? Use the counter-clockwise from east convention.

**Problem 8:**

(Referring to the previous problem.) What will be the airplane's speed (in km/h) relative to the ground?

**Problem 9:**

A boat travels east across a 33 m wide river in 1 seconds. If the river flows .9 m/s north, how far upstream does the boat end up?

**Problem 10:**

A boat moves at 4.5 m/s relative to the water regardless of which direction it travels through the water. If the water in a river is flowing at 1.5 m/s, how long (in seconds) does it take the boat to make a trip across the river if a 284 m displacement downstream is experienced.

Return to: Set B Overview Page || Audio Help Home Page || Set B Sample Problems

Audio Help for Problem: 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10

Retrieve info about: Audio Help || Technical Requirements || Usage Policy || CD-ROM

Return to: Physics 163 Problem Set Page || Physics 163 Home Page