PHYSICS 1 UNIT 1

It is possible to multiply a vector by a scalar.

A 2D vector can have a component equal to zero even when its magnitude is nonzero.

The components of a vector can be different in different coordinate systems.

A 2D vector can have a magnitude equal to zero even when one of its components it nonzero.

The magnitude of a vector can be different in different coordinate systems.

It is possible to add a scalar to a vector.

The direction of a vector can be different in different coordinate systems.

If V3=V1+V2, then V3=V1+V2.

If V3=V1+V2, then V3V1.

If V3=V1+V2, then V4=3V1+3V2 is parallel to V3.

If V3=V1+V2, then V3−V2 is parallel to V1.

If the wall were slightly farther from where the projectile was launched (the projectile still hits it), how would that effect the following? The distance from the ground to where the projectile hit the wall.

If the wall were slightly farther from where the projectile was launched (the projectile still hits it), how would that effect the following? The maximum height of the projectile.

If the wall were slightly farther from where the projectile was launched (the projectile still hits it), how would that effect the following? The magnitude of the x component of the velocity of the projectile when it hits the wall.

If the wall were slightly farther from where the projectile was launched (the projectile still hits it), how would that effect the following? The magnitude of the y component of the velocity of the projectile when it hits the wall.

If the wall were slightly farther from where the projectile was launched (the projectile still hits it), how would that effect the following? The speed of the projectile when it hits the wall.

If the average velocity of an object is zero, then the average speed of the object must also be zero.

If the initial velocity of an object is zero, then the initial speed of the object must be zero.

If the initial speed of an object is zero, then the initial position of the object must be the origin.

If the velocity of an object is zero, then the acceleration of an object must also be zero.

The acceleration of an object can be non-zero when the speed of the object is constant.

The average speed of an object is always equal to the magnitude of the average velocity of the object.

If the acceleration of an object is zero, then the average speed must be equal to the magnitude of the average velocity for the object.

The speed of an object can never be negative.

The velocity of an object can reverse direction when the acceleration of the object is constant.

If an object moves in one dimension with a positive component of acceleration, its speed must be increasing.

A car is initially traveling east through New York City at 10 mph. As the car approaches an intersection it stops and turns left to go north. After traveling one block north the car stops and turns right to once again head east. At the final time the car is traveling east at 10 mph. In what direction is the average acceleration of the car as a result of the motion described above? North East Northeast The average acceleration is zero

physical quantity not described as a vector?

V3 = V1 + V2 What is true about V3? a) V3>0 b) V3<0 c) V3 = 0 d) not enough information e) none makes sense

What is true about V3 = V1 + V2 ? a) V3> V1 + V2 b) V3 < V1 + V2 c) V3 = V1 + V2 d) not enough info

Which is true? V4 = V1 + V2 a) V4x > 0 ; V4y > 0 b) V4x > 0 ; V4y < 0 c) V4x < 0 ; V4y > 0 d) V4x < 0 ; V4y < 0 e) not enough info

What is true about V5 = -V1 + V2 a) V5 = 14 b) V5 = 7sqrt2 c) V5 = 10 d) V5 = 5sqrt2 e) V5 = -14

Vertical components of the velocity (do, dont) depend on one another

Size of any vector is

A ____________ is a vector whose magnitude is 1 and is indicated with a "hat."

Which is equivalent to speed? Magnitude of Average Velocity Average of Magnitude of Velocity

What gives rise to changes in motion, or in other words.. acceleration?

tension forces can only ______ objects

When two objects directly touch one another, then they can exert _____________ on each other.

The direction of kinetic friction ___________ opposes the direction of slipping.

Si unit of Force

resistance to such a change in motion is called

Si unit of mass

The sum of all external forces is called the ___________.

To an inertial observer, an object that has no net external force acting on it will appear to move w a constant velocity.

To an inertial observer, the acceleration of the center of mass of a system (b) is equal to the net force acting on it divided by the inertial mass of the system.

If an object "a" exerts a force on object "b", then object "b" must exert a force of the same form on object "a", which is equal in magnitude and opposite in direction.