Answer:
Speed BA = 18 km/hr.
Explanation:
Given the following data;
Speed AB = 30km/hr
Speed BA = x km/hr
Average speed = 24 km/hr
To find the value of x;
Average speed = (Speed AB + Speed BA)/2
Substituting into the equation, we have
24 = (30 + x)/2
48 = 30 + x
x = 48 - 30
x = 18 km/hr
Answer:
The density ρ of metal block is 8.92g/cm³
So from the given density table this corresponds to copper which has density of 8.92(g/mL)
Explanation:
Oh yeah, I got the correct unit update,
Now this problem bothers on the density of substances
We know that the density of a substance is expressed as
Density ρ= mass/ volume
Given data
Mass of metal block m= 62.44g
Volume of metal block v= 7 cm³
Hence we can find the density of the metal block by plugging in our data into the expression for density
ρ of metal block = 62.44/7
ρ of metal block = 8.92g/cm³
The block is a copper block
Answer:
A stellar collision.
Explanation:
A stellar collision is the coming together of two stars caused by stellar dynamics within a star cluster, or by the orbital decay of a binary star due to stellar mass loss or gravitational radiation, or by other mechanisms not yet well understood.
Q = mass water x specific heat water x delta T.
<span>714,000 = mass water x specific heat water x 30.
Substitute specific heat water and solve for mass water.</span>
Answer:
W = (F1 - mg sin θ) L, W = -μ mg cos θ L
Explanation:
Let's use Newton's second law to find the friction force. In these problems the x axis is taken parallel to the plane and the y axis perpendicular to the plane
Y Axis
N - 
=
N = W_{y}
X axis
F1 - fr - Wₓ = 0
fr = F1 - Wₓ
Let's use trigonometry to find the components of the weight
sin θ = Wₓ / W
cos θ = W_{y} / W
Wₓ = W sin θ
W_{y} = W cos θ
We substitute
fr = F1 - W sin θ
Work is defined by
W = F .dx
W = F dx cos θ
The friction force is parallel to the plane in the negative direction and the displacement is positive along the plane, so the Angle is 180º and the cos θ= -1
W = -fr x
W = (F1 - mg sin θ) L
Another way to calculate is
fr = μ N
fr = μ W cos θ
the work is
W = -μ mg cos θ L
