Answer:
the angle the ladder makes with the floor as seen by an observer on Earth is 71.9°
Explanation:
Given the data in the question and as illustrated in the diagram below.
speed of the ship v = 0.90c
base of the ladder from the wall x₀ = 3.0 m
top of the later above the floor y = 4.0 m
we determine angle θ.
from the diagram,
tanθ = y/x₀
tanθ = y / x₀√( 1 - v²/c² )
we substitute
tanθ = 4.0 / 3.0√( 1 - ((0.9c)²/c²) )
tanθ = 4.0 / 3.0√( 1 - ((0.9²)c²/c²) )
tanθ = 4.0 / 3.0√( 1 - (0.9²) )
tanθ = 4.0 / 3.0√( 1 - 0.81 )
tanθ = 4.0 / 3.0√0.19
tanθ = 4.0 / 1.30766968
tanθ = 3.058876
θ = tan⁻¹( 3.058876 )
θ = 71.8965 ≈ 71.9°
Therefore, the angle the ladder makes with the floor as seen by an observer on Earth is 71.9°
Answer:
There is absolutely No relationship between the weight of an object (which is constant) and the frictional force. If a block is sliding on a surface, that surface will be exerting a force on the block. That force can be resolved into a component parallel to the surface (which we call the frictional component), and a component perpendicular to the surface (called the normal component). For many situations, we find experimentally that the frictional component is approximately proportional to the normal component. The frictional component divided by the normal component is defined to be a quantity called the coefficient of kinetic or sliding friction. The coefficient of kinetic friction obviously depends on the nature of the surfaces involved. The normal component on an object can be decreased if you pull in the direction of the normal component (the weight does not change). However pulling this way on the object not only decreases the normal component, but it also decreases the frictional component since they are proportional. This is why it is easier to slide something if you pull up on it while you push it. If you push down, the normal and frictional components increase so it is harder to slide the object. The weight of an object is the downward force exerted by Earth’s gravity on that object, and it does not change no matter how you push or pull on the object.
It’s a because b makes more since shown as the magnet
Three different units of energy is
1. Joule: is is SI unit of measuring thermal energy or heat
2. Calorie: this system of energy is used when we take CGS system of mass and specific heat capacity
3. BTU: this system is known as british thermal unit which is used in measuring engineering calculations
