Answer:
friction can be used to slow things down but it can also be harmful because it can cause fire to start
Answer:
f = 692 N
Explanation:
given data:
f =800N
a =1.2 m s^{2}
m= 90 kg
from newton's second law
net force 
therefore we have from above equation
ma =F - f
putting all value to get force of friction
1.2*90 = 800 - f
f = 692 N
Elastic potential energy stored in a spring is
(1/2) · (spring constant) · (stretch or compress)² .
PE = (1/2) · (100 N/m) · (0.1 m)²
PE = (50 N/m) · (0.01 m²)
PE = (50 · 0.01) (N · m / m²)
PE = 0.5 N · m
PE = 0.5 Joule
Answer:
Q = 200800 Joules.
Explanation:
Given the following data;
Mass = 4kg
Initial temperature = 30.0°C
Final temperature = 90.0°C
Specific heat capacity of glass = 837 J/kg°C
To find the quantity of heat absorbed;
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.
dt = T2 - T1
dt = 90 - 30
dt = 60°C
Substituting the values into the equation, we have;
Q = 200800 Joules.
Therefore, the amount of heat absorbed is 200800 Joules.