Answer:
The magnitude of the frictional force is 48.02 N
Explanation:
Mass of box = 20 kg
Weight of the box (Normal reaction) = mass × acceleration due to gravity = 20 ×9.8 = 196 N
Horizontal force applied = 48 N
Coefficient of friction = horizontal force ÷ normal reaction = 48 ÷ 196 = 0.245
Frictional force = coefficient of friction × normal reaction = 0.245 × 196 N = 48.02 N
Answer:



Explanation:
Frequency of the disc is given by the

here we know that


now we have


Now we know that its angular speed is 754 rad/s
now to find the time to turn by 90 degree is given as


Now the angular acceleration is given as



Particles transfer energy physically from one to the other either horizontally in a longitudinal wave, vertically in a transverse wave, or in circles in a surface wave. Waves can also be electromagnetic, which are always transverse and do not require a medium to propagate, like light waves traveling through space.
Answer:
Heat energy required = 252000J or 252KJ.
Explanation:
<u>Given the following data;</u>
Mass = 3kg
Temperature = 20ºC
Specific heat capacity of water = 4200 J/kg°C
To find the heat energy required;
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.
- t represents the temperature.
Substituting into the equation, we have;
Q = 252000 Joules or 252 Kilojoules.