Answer:
Explanation:
for baseball
(a) Let the mass of the baseball is m.
radius of baseball is r.
Total kinetic energy of the baseball, T = rotational kinetic energy + translational kinetic energy
T = 0.5 Iω² + 0.5 mv²
Where, I be the moment of inertia and ω be the angular speed.
ω = v/r
T = 0.5 x 2/3 mr² x v²/r² + 0.5 mv²
T = 0.83 mv²
According to the conservation of energy, the total kinetic energy at the bottom is equal to the total potential energy at the top.
m g h = 0.83 mv²
where, h be the height of the top of the hill.
9.8 x h = 0.83 x 6.8 x 6.8
h = 3.93 m
(b) Let the velocity of juice can is v'.
moment of inertia of the juice can = 1/2mr²
So, total kinetic energy
T = 0.5 x I x ω² + 0.5 mv²
T = 0.5 x 0.5 x m x r² x v²/r² + 0.5 mv²
m g h = 0.75 mv²
9.8 x 3.93 = 0.75 v²
v = 7.2 m/s
Using the principle of floatation.
u = w............(a)
Upthrust of fluid is equal to the weight of the object.
Let the volume of the wood be V.
The upthrust u, is related to the volume submerged in water, and that is 1/5 of it volume, that is (1/5)V = 0.2V
Formula for upthrust, u = vdg
where v = volume of fluid displaced
d = density of fluid
g = acceleration due to gravity
weight, w = mg
where m = mass
g = acceleration due to gravity
From (a)
u = w
vdg = mg Cancel out g
vd = m
The v is equal to 0.2V, which is the submerged volume. Notice that the small letter v is volume of fluid displaced, and capital V is the volume of the solid.
d is density of fluid which is water in this case, 1000 kg/m³
0.2V * 1000 = m
200V = m
Hence the mass of the object is 200V kg.
But Density of solid = Mass of solid / Volume of solid
= 200V / V
= 200 kg/m³
Density of solid = 200 kg/m³
Answer:
128 m
Explanation:
From the question given above, the following data were obtained:
Horizontal velocity (u) = 40 m/s
Height (h) = 50 m
Acceleration due to gravity (g) = 9.8 m/s²
Horizontal distance (s) =?
Next, we shall determine the time taken for the package to get to the ground.
This can be obtained as follow:
Height (h) = 50 m
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) =?
h = ½gt²
50 = ½ × 9.8 × t²
50 = 4.9 × t²
Divide both side by 4.9
t² = 50 / 4.9
t² = 10.2
Take the square root of both side
t = √10.2
t = 3.2 s
Finally, we shall determine where the package lands by calculating the horizontal distance travelled by the package after being dropped from the plane. This can be obtained as follow:
Horizontal velocity (u) = 40 m/s
Time (t) = 3.2 s
Horizontal distance (s) =?
s = ut
s = 40 × 3.2
s = 128 m
Therefore, the package will land at 128 m relative to the plane
Vas happenin!!
1. =
2. >
3. <
4. <
5. <
6. >
Hope this helps *smiles*