When an effervescent tablet is dropped in water, what indicates that a chemical change is occurring?

a. the evolution of a gas

b. the condensation of a gas

c. the melting of a solid

d. the subliming of a solid

You are standing on the sidewalk and see a bus drive by. What would be an ideal frame of reference? A bird flying overhead A jogger running along the sidewalk A car driving alongside the bus A tree across the street

During actual sound waves, what is being spread apart from us to hear sound?

A 2.5 kg ball rolls forward at 10.0 m/s. What is the ball's momentum?

Which is a correct example of the principle of conservation of momentum? A) reversing of a car at a dead end B) conversion of radio waves to sound C) deforming of a balloon on being burst D) bouncing of a basketball off the board

Intr-o grupa, 3 elevi au masurat lungimea unui creion si au obtinut urmatoarele valori: 16,2 cm; 16,5 cm si respective 16,1 cm. Aflati valoarea medie a valorilor masurate si erorile obtinute de fiecare elev.

Dolphins and other sea creatures can leap to great heights by swimming straight up and exiting the water at a high speed. A 200 kg dolphin leaps straight up to a height of 7.8 m.

An example of renewable energy resource is ... A - uranium B - Wind C - natural gas

The power of a 1.5-volt alkaline cell varies with the number of hours of operation. A brand new D-cell can deliver as much as 13 A through a copper wire connected between terminals. Determine the power of a brand new D-cell.

You measure a watch's hour and minute hands to be 7.4 mm and 12.1 mm long, respectively. Part A In one day, by how much does the distance traveled by the tip of the minute hand exceed the distance traveled by the tip of the hour hand?

Describe the possible long term impact of a catastrophic event