Explain the energy, temperature, and mass changes that occur when
a- an ice at 0°c, starts to melt (3 marks)
b- a saucepan filled with soup at 15°c is heated on a gas hob (3 marks)
c- boiling water from a kettle at 100°c turns to water vapour

20. threshold braking in the vehicle's braking system occurs when a. the brake pedal is pushed, heel on floorboard, with full foot pressure. b. the brakes are exerting full braking power, without traction loss. c. the driver begins pushing down the brake pedal, with moderate slowdown. d. the brakes just begin to take hold with a gradual slowdown.

Engineers find a new metal that is stronger than steel but much lighter. this material is also significantly cheaper than what is currently used for most aircraft, available in large quantities, and easy to manufacture. the engineers are excited because this new material will lower the costs of buying and operating airplanes for companies. what is probably the best step for the engineers to make next?

What is the weight of a feather (mass = 0.0001 kg) that floats through earth's and the moon's atmospheres?