To make sure that we have enough resourses to sustain ourselves. You see, if we use up, say, all water on earth, then obviously we won't have any more and we'll die.
A )
t 1 = 2 h, t 2 = 6 h
Δ t = t 2 - t 1 = 6 - 2 = 4 h
54 = 50 + a Δ t
54 = 50 + 4 a
4 a = 54 - 4
4 a = 4
a = 4 : 4
a = 1 km/h²
v o = 48 km/h
An equation that can be used to describe the velocity of the car at the different times is:
v = 48 + t
B ) The graph is in the attachment.
Answer:
The extension of the wire is 0.362 mm.
Explanation:
Given;
mass of the object, m = 4.0 kg
length of the aluminum wire, L = 2.0 m
diameter of the wire, d = 2.0 mm
radius of the wire, r = d/2 = 1.0 mm = 0.001 m
The area of the wire is given by;
A = πr²
A = π(0.001)² = 3.142 x 10⁻⁶ m²
The downward force of the object on the wire is given by;
F = mg
F = 4 x 9.8 = 39.2 N
The Young's modulus of aluminum is given by;
Where;
Young's modulus of elasticity of aluminum = 69 x 10⁹ N/m²
Therefore, the extension of the wire is 0.362 mm.
Becomes older
Explanation:
As sea floor spreading occurs at divergent margins, the oceanic plate becomes older. Younger plate margin are the closest to the margin whereas the older plates bushes backward away from the spreading centers.
- The idea that the sea floor spreads was postulated by Harry Hess shortly after the second world war around the 1960's.
- At divergent margins new crust materials from the mantle are brought to the surface.
- They crystallize and settle at the flanks of plate margins.
- Older ones are pushed backward away from the margin into far away subduction zones.
Learn more:
Sea floor spreading brainly.com/question/9912731
#learnwithBrainly
The only vertical forces are weight and normal force, and they balance since the surface is horizontal. The horizontal forces are the applied force (uppercase F) in the direction the block slides and the frictional force (lowercase f) in the opposite direction.
Apply Newton's 2nd Law in the horizontal direction:
ΣF = ma
F - f = ma
where f = µmg
F - µmg = ma
F = m(a +µg)
F = (20 kg)(1.4 m/s² + 0.28(9.8 m/s²)
F = 83 N
