Answer:
Explanation:
In microwave, there are waves called "microwaves" as per the name. So, The heating of food is done with the help of waves. Radiation is "the transfer of heat through waves". That is why the process of heating food in a microwave is "Radiation".
Answer:
a) t = 4.14 s
b) Speed with which it hits the ground = 40.58 m/s
Explanation:
Using the equations of motion,
g = 9.8 m/s², y = H = 84 m,
Initial velocity, u = 0 m/s,
final velocity, v = ?
Total Time of fall, t = ?
a) y = ut + gt²/2
84 = 0 + 9.8t²/2
4.9t² = 84
t² = 84/4.9
t = 4.14 s
b) v = u + gt
v = 0 + (9.8 × 4.14)
v = 40.58 m/s
The deceleration of the car is 3 m/s².
<u>Explanation:</u>
So the initial velocity of the car is given as 12 m/s. As the car is said to slow down and then it stops after 4 seconds, so the final velocity is zero.
We know that the acceleration acting on any object to stop the motion of that object is termed as deceleration or negative acceleration.
This is because, acceleration is the ratio of change in velocity to time taken for that change in velocity.
So.,
So the deceleration of the car is 3 m/s².
Answer:
T2 = 355.92 Kelvin or 82.92°C
Explanation:
Given the following data;
Mass = 567g to kilograms = 567/1000 = 0.567 kg
Quantity of heat = 18,100J
Initial temperature = 15°C to Kelvin = 15 + 273 = 288K
Specific heat capacity of iron = 470j/kg•k
To find the final temperature;
Heat capacity is given by the formula;
Where;
- Q represents the heat capacity or quantity of heat.
- m represents the mass of an object.
- c represents the specific heat capacity of water.
- dt represents the change in temperature.
Making dt the subject of formula, we have;
Substituting into the equation, we have;
dt = 67.92K
Now, the final temperature T2 is;
But, dt = T2 - T1
T2 = dt + T1
T2 = 67.92 + 288
T2 = 355.92 Kelvin or 82.92°C