Answer:
0.45
Explanation:
Sum of forces in the y direction:
∑F = ma
N − mg = 0
N = mg
There are friction forces in two directions: centripetal and tangential. The centripetal acceleration is:
ac = v² / r
ac = (31 m/s)² / 333 m
ac = 2.89 m/s²
The total acceleration is:
a = √(ac² + at²)
a = √((2.89 m/s²)² + (3.32 m/s²)²)
a = 4.40 m/s²
Sum of forces:
∑F = ma
Nμ = ma
mgμ = ma
μ = a / g
μ = 4.40 m/s² / 9.8 m/s²
μ = 0.45
Yes. According to the coach's mathematical criteria, Tommy had a great season.
Sadly, Tommy doesn't even know it. His tone-deaf coach decided to describe success in terms that are absurd for 7-yr-olds, as well as for most of their parents.
Answer: The ball (option A)
Explanation: change in momentum is defined by the formulae m(v - u) where m = mass of object, v = final velocity and u = initial velocity.
For the ball, it hits the ground and bounces back with the same speed, that's final velocity equals initials (v = - u)
Change in momentum = m( -u- u) = m(-2u) = m(-2u) = -2mu
For the clay, it final velocity is zero since it sticks to the floor, hence (v =0)
m(v - u) = m(0 - u) = - mu.
-2mu (change in momentum from the ball) is greater than - mu ( change in momentum of clay)
Answer:
The earthquake occurred at a distance of 1122 km
Explanation:
Given;
speed of the P wave, v₁ = 8.5 km/s
speed of the S wave, v₂ = 5.5 km/s
The distance traveled by both waves is the same and it is given as;
Δx = v₁t₁ = v₂t₂
let the time taken by the wave with greater speed = t₁
then, the time taken by the wave with smaller speed, t₂ = t₁ + 1.2 min, since it is slower.
v₁t₁ = v₂t₂
v₁t₁ = v₂(t₁ + 1.2 min)
v₁t₁ = v₂(t₁ + 72 s)
v₁t₁ = v₂t₁ + 72v₂
v₁t₁ - v₂t₁ = 72v₂
t₁(v₁ - v₂) = 72v₂
The distance traveled is given by;
Δx = v₁t₁
Δx = (8.5)(132)
Δx = 1122 km
Therefore, the earthquake occurred at a distance of 1122 km
