Exam 4: Motion in Two and Three Dimensions

A boy on the edge of a vertical cliff 20 m high throws a stone horizontally outwards with a speed of 20 m/s.It strikes the ground at what horizontal distance from the foot of the cliff? Use g = 10 m/s²

A boat is able to move through still water at 20 m/s.It makes a round trip to a town 3.0 km upstream.If the river flows at 5 m/s, the time required for this round trip is:

A stone is thrown outward from the top of a 59.4-m high cliff with an upward velocity component of 19.5 m/s.How long is the stone in the air? Assume that it lands on the ground below the cliff, and that the ground below the cliff is flat.

Two objects are traveling around different circular orbits with constant speed.They both have the same acceleration but object A is traveling twice as fast as object B.The orbit radius for object A is _______ the orbit radius for object B.

A girl wishes to swim across a river to a point directly opposite as shown.She can swim at 2 m/s in still water and the river is flowing at 1 m/s.At what angle $\theta$ with respect to the line joining the starting and finishing points should she swim?

Two projectiles are in flight at the same time.The acceleration of one relative to the other:

What is the difference between speed and velocity?

A car rounds a 20-m radius curve at a speed of 10 m/s.The magnitude of its acceleration is:

A projectile is fired over level ground with an initial velocity that has a vertical component of 20 m/s and a horizontal component of 30 m/s.Using g = 10 m/s², the distance from launching to landing points is:

A particle moves at constant speed in a circular path.The instantaneous velocity and instantaneous acceleration vectors are:

A toy racing car moves with constant speed around the circle shown below.When it is at point A its coordinates are x = 0, y = 3m and its velocity is (6 m/s) .When it is at point B its velocity and acceleration are:

An object moves from x = -2.1 m, y = 3.7 m, z = 1.4 m to x = 3.3 m, y = -1.1 m, z = 4.2 m in a time of 5.3 s.What is its average velocity?

A stone thrown from the top of a tall building follows a path that is:

A stone is tied to a 0.50-m string and whirled at a constant speed of 4.0 m/s in a vertical circle.The acceleration at the bottom of the circle is:

A particle goes from x = -2 m, y = 3 m, z = 1 m to x = 3 m, y = -1 m, z = 4 m.Its displacement is:

Two bodies are falling with negligible air resistance, side by side, above a horizontal plane.If one of the bodies is given an additional horizontal acceleration during its descent, it:

From your window you can see a high-rise building several blocks away.You check the map and see that the building is 560 m away from you in a straight line, in a direction 30° south of east.However, the roads are all east-west and north-south.If you want to walk from your house to the building, how far in each direction do you have to walk?

A stone is tied to a 0.50-m string and whirled at a constant speed of 4.0 m/s in a vertical circle.Its acceleration at the top of the circle is:

A stone is tied to the end of a string and is swung with constant speed around a horizontal circle with a radius of 1.5 m.If it makes two complete revolutions each second, its acceleration is:

The position of an object as a function of time is given in meters by x = (at + bt²) + (ct) .What is its velocity as a function of time?