Answer:
a) t=1s
y = 10.1m
v=5.2m/s
b) t=1.5s
y =11.475 m
v=0.3m/s
c) t=2s
y =10.4 m
v=-4.6m/s (The minus sign (-) indicates that the ball is already going down)
Explanation:
Conceptual analysis
We apply the free fall formula for position (y) and speed (v) at any time (t).
As gravity opposes movement the sign in the equations is negative.:
y = vi*t - ½ g*t2 Equation 1
v=vit-g*t Equation 2
y: The vertical distance the ball moves at time t
vi: Initial speed
g= acceleration due to gravity
v= Speed the ball moves at time t
Known information
We know the following data:
Vi=15 m / s
t=1s ,1.5s,2s
Development of problem
We replace t in the equations (1) and (2)
a) t=1s
=15-4.9=10.1m
v=15-9.8*1 =15-9.8 =5.2m/s
b) t=1.5s
=22.5-11.025=11.475 m
v=15-9.8*1.5 =15-14.7=0.3m/s
c) t=2s
= 30-19.6=10.4 m
v=15-9.8*2 =15-19.6=-4.6m/s (The minus sign (-) indicates that the ball is already going down)
Answer:
15.7 m
Explanation:
m = mass of the sled = 125 kg
v₀ = initial speed of the sled = 8.1 m/s
v = final speed of sled = 0 m/s
F = force applied by the brakes in opposite direction of motion = 261
d = stopping distance for the sled
Using work-change in kinetic energy theorem
- F d = (0.5) m (v² - v₀²)
- (261) d = (0.5) (125) (0² - 8.1²)
d = 15.7 m
Answer
given,
diameter,d₁ = 7.5 cm
d₂ = 4.5 cm
P₁ = 32 kPa
P₂ = 25 kPa
Assuming, we have calculation of flow in the pipe
using continuity equation
A₁ v₁ = A₂ v₂
π r₁² v₁ = π r₂² v₂
Applying Bernoulli's equation
v₂ = 4.01 m/s
fluid flow rate
Q = A₂ V₂
Q = π (0.0225)² x 4.01
Q = 6.38 x 10⁻³ m³/s
flow in the pipe is equal to 6.38 x 10⁻³ m³/s
Answer:
The total volume of the air is 1000 cubic centimeters.
Explanation:
Since the bicycle pump and the bicycle tyre have the same pressure, then the total volume of the air is the sum of the volume of each element, then we translate this into the following artihmetical expression:
The total volume of the air is 1000 cubic centimeters.
