Answer:
450 kJ
Explanation:
Q = mCΔT
where Q is heat (energy),
m is mass,
C is specific heat capacity,
and ΔT is the temperature change.
Q = (1.2 kg) (4180 J/kg/°C) (100°C − 10°C)
Q = 451,440 J
Q ≈ 450 kJ
Answer:
The density of one halves 11.3 g / cm cube
Explanation:
Density remain same because cutting the bar in half , mass and volume will decrease to half so density will not change .
density = 
Answer:
Chief Hopper
Explanation:
Mike travels at a constant speed of 3.1 m/s. To find how long it takes him to reach the school, we need to find the distance he travels. We can do this using Pythagorean theorem.
a² + b² = c²
(1000 m)² + (900 m)² = c²
c ≈ 1345 m
So the time is:
v = d / t
3.1 m/s = 1345 m / t
t ≈ 434 s
Next, Chief Hopper travels a total distance of 1900 m, starting at rest and accelerating at 0.028 m/s². So we can use constant acceleration equation to find the time.
d = v₀ t + ½ at²
1900 m = (0 m/s) t + ½ (0.028 m/s²) t²
t ≈ 368 s
So Chief Hopper reaches the school first, approximately 66 seconds before Mike does.
Answer:
Heavier person
Explanation:
Work = force × distance. In this case, force = weight and distance = height of the stairs. For both people, the height of the stairs is the same. Since the heavier person has more weight, they did more work.
