Answer:
157.9 kg
Explanation:
Density: This can be defined as the ratio of the mass of a body and it's volume.
The S.I unit of density is kg/m³.
From the question,
Density = Mass/volume
D = m/v............................ Equation 1
Where D = Density of gold, m = mass of gold, v = volume of gold.
make m the subject of the equation
m = Dv.................... Equation 2
Since the gold is a cube,
v = l³................... Equation 3
Where l = length of the gold cube.
Substitute equation 3 into equation 2
m = Dl³............... Equation 4
Given: D = 19300 kg/m³, l = 0.2015 m
Substitute into equation 4
m = 19300(0.2015)³
m = 157.9 kg.
Coffee mug is cylindrical shape. Therefore,
Volume of mug = volume of cylinder = πr²h
r = inner radius of mug. h = height of coffee = 6 cm.
Density of coffee = Density of water = 1 g/ml
Therefore, volume of coffee = mass/density = 400/1 = 400 ml = 400 cm³
Volume of coffee = πr²h
400= πr²(6)
r² = 21.23
r = inner radius of mug = 4.607 cm
a. 4.52 m/s south
Velocity is a vector, whose magnitude is defined as the ratio between the displacement of the object and the time taken for the displacement to occur:
where
d is the displacement
t is the time
Velocity is a vector, so it also has a direction, which corresponds to that of the displacement.
For the ball in this problem,
d = 9.5 m south
t = 2.1 s
Substituting, we find:
and the directiion is the same as the displacement (south).
b. 4.52 m/s north
For this part, we must keep in mind that the speed is the magnitude of the velocity; however, speed is a scalar, so it does not have a direction.
Here we are told that the tennis ball travels at constant speed, so on its way back from Liam to Katie the ball's velocity is still the same as before, therefore
However, this time the direction is opposite to before, since the ball is travelling in the opposite direction.
Therefore, the ball's velocity when Liam returns Katie's service is
4.52 m/s north
Answer:
The lid becomes tighter
It becomes tighter because metals have a lower heat capacity than glass meaning their temperature drops (or increases) much faster than glass for the same energy change. So in this example, the metal will contract faster than the glass causing it to be more tighter around the glass.
Acceleration equals the change in velocity divided by time
