Answer:
Right
Explanation:
electromagnetic waves can travel through space (a vacuum) because it doesn't need a medium and its particles to propagate whereas a mechanical wave needs a medium to propagate. For example sound is a mechanical wave, sound vibrates off a mediums particles to propagate and for sound to be heard and travel
Answer:

Explanation:
Given the following data;
Frequency = 4.0 x 10⁹ Hz
Planck's constant, h = 6.626 x 10-34 J·s.
To find the energy of the electromagnetic wave;
Mathematically, the energy of an electromagnetic wave is given by the formula;
E = hf
Where;
E is the energy possessed by a wave.
h represents Planck's constant.
f is the frequency of a wave.
Substituting the values into the formula, we have;


The metal conducts the heat, which makes cooking easier.
Answer:
1. The final velocity of the truck is 15 m/s
2. The distance travelled by the truck is 37.5 m
Explanation:
1. Determination of the final velocity
Initial velocity (u) = 0 m/s
Acceleration (a) = 3 m/s²
Time (t) = 5 s
Final velocity (v) =?
The final velocity of the truck can be obtained as follow:
v = u + at
v = 0 + (3 × 5)
v = 0 + 15
v = 15 m/s
Therefore, the final velocity of the truck is 15 m/s
2. Determination of the distance travelled
Initial velocity (u) = 0 m/s
Acceleration (a) = 3 m/s²
Time (t) = 5 s
Distance (s) =?
The distance travelled by the truck can be obtained as follow:
s = ut + ½at²
s = (0 × 5) + (½ × 3 × 5²)
s = 0 + (½ × 3 × 25)
s = 0 + 37.5
s = 37.5 m
Therefore, the distance travelled by the truck is 37.5 m
Answer:
The specific heat capacity of iridium = 0.130 J/g°C
Explanation:
Assuming no heat losses to the environment and to the calorimeter,
Heat lost by the iridium sample = Heat gained by water
Heat lost by the iridium sample = mC ΔT
m = mass of iridium = 23.9 g
C = specific heat capacity of the iridium = ?
ΔT = change in temperature of the iridium = 89.7 - 22.6 = 67.1°C
Heat lost by the iridium sample = (23.9)(C)(67.1) = (1603.69 C) J
Heat gained by water = mC ΔT
m = mass of water = 20.0 g
C = 4.18 J/g°C
ΔT = 22.6 - 20.1 = 2.5°C
Heat gained by water = 20 × 4.18 × 2.5 = 209 J
Heat lost by the iridium sample = Heat gained by water
1603.69C = 209
C = (209/1603.69) = 0.130 J/g°C