# What is at rest relative to a seated passenger in a moving car?

## What is at rest relative to a seated passenger in a moving car?

– The seat –> correct. The seat is moving at the same velocity of the passenger, so it is at rest in his frame of reference.

## Which distance can be most accurately measured with a ruler?

The answer is a width of a textbook. It is usually has centimeter and millimeter units on it. Since rulers are most commonly 15 or 30 cm long, it could only be used to measure the length or width of small things like small tin, or the length of a piece of paper.

**Which example describes constant acceleration?**

For example, if the velocity of a particle moving in a straight line changes uniformly (at a constant rate of change) from 2 m/s to 5 m/s over one second, then its constant acceleration is 3 m/s2.

### What is the SI unit best suited for measuring the height of a building?

Choosing Appropriate Units of Measure

Quantity | Appropriate unit of measure |
---|---|

Height of a person | Feet and inches, or centimeters |

Weight of a person | Pounds or kilograms |

Height of a high-rise building | Meters or feet |

Height of a mountain peak | Meters or feet |

### In which situation can you be at rest and moving at the same time?

Explanation: If you are sat on a moving vehicle then you are at rest relative to the vehicle, but moving relative to the ground outside. Even cooler, you are both at rest and moving right now – at rest relative to the earth, but because the earth is moving, moving relative to the rest of the solar system.

**What 3 things can cause acceleration?**

There are three ways an object can accelerate: a change in velocity, a change in direction, or a change in both velocity and direction.

## Is the ratio of the distance an object moves to?

Speed- The ratio of the distance an object moves to the amount of time the object moves.

## Can you have negative acceleration?

This represents an object that has a constant speed. It is not speeding up or slowing down, so it has zero acceleration. Because the velocity/speed of this object is decreasing over time, this means there is a negative acceleration.

**What are the units of length in order from smallest to largest?**

In order from smallest to largest, they rank: millimeter (mm), centimeter (cm), decimeter (dm), and meter (m). Here, the millimeter (mm) is the smallest unit of measure.

### What is SI unit of mass?

The SI unit of mass is the kilogram (kg). In science and technology, the weight of a body in a particular reference frame is defined as the force that gives the body an acceleration equal to the local acceleration of free fall in that reference frame.

### How far will an object move in one second if its average speed is 5 m s?

How far will an object move in one second if its average speed is 5m/s? 5 m. 5 m (its average speeed would be 5 m/s).

**How is velocity different than speed?**

Speed is the time rate at which an object is moving along a path, while velocity is the rate and direction of an object’s movement. Put another way, speed is a scalar value, while velocity is a vector. In its simplest form, average velocity is calculated by dividing change in position (Δr) by change in time (Δt).