Question

1. identify for each of the following news stories, determine whether the objects speed or velocity is given: the world record for the hundred - meter dash is about 10 m/s; the wind is 30 km/h from the northwest; a 200,000 kg train was traveling north at 70 km/h when it derailed; a car was issued a ticket for traveling at 140 km/h on the interstate.

Explanation:

Step1: Recall the definitions

Speed is a scalar quantity (magnitude only), velocity is a vector quantity (magnitude and direction).

Step2: Analyze each case

• The world - record for the hundred - meter dash: It has only magnitude (about 10 m/s), so it is speed.
• The wind is 30 km/h from the northwest: It has magnitude (30 km/h) and direction (northwest), so it is velocity.
• A 200,000 kg train was traveling north at 70 km/h: It has magnitude (70 km/h) and direction (north), so it is velocity.
• A car was issued a ticket for traveling at 140 km/h on the interstate: It has only magnitude (140 km/h), so it is speed.

Answer:

The world - record for the hundred - meter dash: Speed; The wind is 30 km/h from the northwest: Velocity; A 200,000 kg train was traveling north at 70 km/h: Velocity; A car was issued a ticket for traveling at 140 km/h on the interstate: Speed