Answer:
a) 
& 
b) 
c) 
Explanation:
Given:
mass of the book, 
combined mass of the student and the skateboard, 
initial velocity of the book, 
angle of projection of the book from the horizontal, 
a)
velocity of the student before throwing the book:
Since the student is initially at rest and no net force acts on the student so it remains in rest according to the Newton's first law of motion.
where:
initial velocity of the student
velocity of the student after throwing the book:
Since the student applies a force on the book while throwing it and the student standing on the skate will an elastic collision like situation on throwing the book.
where:
final velcotiy of the student after throwing the book
b)
c)
Since there is no movement of the student in the vertical direction, so the total momentum transfer to the earth will be equal to the momentum of the book in vertical direction.
Let t=time to reach the ground=8 secs, g= acceleration of gravity. The speed v on reaching the ground is gt=8g=78.4 m/s where g=9.8 m/s/s approx.
Answer:
1069.38 gallons
Explanation:
Let V₀ = 1.07 × 10³ be the initial volume of the gasoline at temperature θ₁ = 52 °F. Let V₁ be the volume at θ₂ = 97 °F.
V₁ = V₀(1 + βΔθ) β = coefficient of volume expansion for gasoline = 9.6 × 10⁻⁴ °C⁻¹
Δθ = (5/9)(97°F -52°F) °C = 25 °C.
Let V₂ be its final volume when it cools to 52°F in the tank is
V₂ = V₁(1 - βΔθ) = V₀(1 + βΔθ)(1 - βΔθ) = V₀(1 - [βΔθ]²)
= 1.07 × 10³(1 - [9.6 × 10⁻⁴ °C⁻¹ × 25 °C]²)
= 1.07 × 10³(1 - [0.024]²)
= 1.07 × 10³(1 - 0.000576)
= 1.07 × 10³(0.999424)
= 1069.38 gallons
As a wave moves through a medium, particles are displaced and return to their normal position after the wave passes.
Explanation:
A wave is a traveling disturbance that carries energy from one location to another. All waves move in straight lines outward and away from the source of a disturbance. Like the radiating circular ripples, the waves of water carry energy away from where a rock was dropped into the pond.
Waves can move as a single pulse or as a continuous series of waves, carrying energy away from its source. A pulse is a single disturbance, wave, or ripple that moves outward from the point of disturbance. A train of waves are many waves emitted over and over again from a single source.
As waves travel through matter, they will temporarily displace the molecules or particles in matter up-and-down or side-to-side. Waves move the energy but they do not carry the matter with them longitudinally as they move through matter. Once the disturbance passes, the medium will return to its original state or position.
Therefore, as the waves move through a medium, particles are displaced and return to their normal position after the wave passes.
