Answer:
hence option A is correct
Explanation:
heat required from -9°C to 0°C ice = mass × specific heat of ice ×change in temperature
heat required from -9°C to 0°C ice = 7×2100×9 =132300 J =0.1323 MJ
( HERE SPECIFIC HEAT OF ICE IS A CONSTANT VALUE OF 2100
J/(kg °C )
heat required from 0°C ice to 0°C water = mass× specific heat of fusion of ice
= 7×3.36×10^5
= 2.352 × 10^6 J
= 2.352 MJ
TOTAL HEAT ENERGY REQUIRED = 0.1323 MJ +2.352 MJ
= 2.4843 MJ
hence option A is correct
True: All matter on earth is made up of atoms.
False: Subatomic particles don't identify an element. I give you an electron. Can you tell me where it came from?
False: (1/2) A neutron has no charge [That's the True part]. It identifies the element. (Not true).
True: description of an electron.
True: description of a proton
Answer:
Speed of bike = 2.5 km/h
Distance travel = 1,000 km (Approx.)
Explanation:
Given:
Distance cover by Helmut = 5 km
Time taken = 2 hour
Find:
Speed of bike
Computation:
Speed = Distance / Time
Speed of bike = 5 / 2
Speed of bike = 2.5 km/h
Given:
Speed of plane = 250 km/h
time taken = 3 hr 58 min = 3.967 hr
Find:
Distance travel
Computation:
Distance = Speed x time
Distance travel = 250 x 3.967
Distance travel = 991.669
Distance travel = 1,000 km (Approx.)
