Answer:
11 m/s
Explanation:
Draw a free body diagram. There are two forces acting on the car:
Weigh force mg pulling down
Normal force N pushing perpendicular to the incline
Sum the forces in the +y direction:
∑F = ma
N cos θ − mg = 0
N = mg / cos θ
Sum the forces in the radial (+x) direction:
∑F = ma
N sin θ = m v² / r
Substitute and solve for v:
(mg / cos θ) sin θ = m v² / r
g tan θ = v² / r
v = √(gr tan θ)
Plug in values:
v = √(9.8 m/s² × 48 m × tan 15°)
v = 11.2 m/s
Rounded to 2 significant figures, the maximum speed is 11 m/s.
Answer:
Manganese oxide prevents polarisation in dry cells. - Polarization is a defect that occurs in simple electric cells due to the accumulation of hydrogen gas around the positive electrode. ... - MnO2 reacts with H2 and forms water as byproduct, so depolarization doesn't occur.
Answer:
0.8s
Explanation:
Given parameters:
Height of shelf = 3m
Unknown:
Time it will take to hit the ground = ?
Solution:
To solve this problem, we use the expression below;
x = ut + gt²
x is the height
u is the initial velocity = 0m/s
g is the acceleration due to gravity = 9.8m/s²
t is the time taken = ?
Now insert the parameters and solve for t;
3 = (0 x t) +( x 9.8 x t²)
3 = 4.9t²
t² = 0.6
t = 0.8s
<span>virtual, upright, and magnified</span>
Answer:
Ice is water in solid phase, in this phase, the particles are very close together and relatively in fixed positions.
As the temperature starts to increase (thermal energy), also does the kinetic energy of the particles (so we have a change from thermal energy to kinetic energy), so they start to move "more", and the position of the particles starts to be less "fixed". There is a point where the particles have enough energy, and this point is where the phase of the water changes from solid to liquid phase (the fusion point). After this point the water can not hold his shape, and takes the shape of the container where it is.