Explanation:
Given:
Δx = -100
v = 10
a = 20
To find v₀, use a kinematic equation that's independent of time.
v² = v₀² + 2aΔx
(10)² = v₀² + 2(20)(-100)
100 = v₀² − 4000
v₀² = 4100
v₀ = ±64.0
As your teacher said, v₀ can't be +64.0. So v₀ = -64.0.
Next, to find time, use a kinematic equation that's independent of initial velocity.
Δx = vt − ½ at²
-100 = (10) t − ½ (20) t²
-100 = 10 t − 10 t²
-10 = t − t²
t² − t − 10 = 0
Solve with quadratic formula:
t = [ -(-1) ± √((-1)² − 4(1)(-10)) ] / 2(1)
t = (1 ± √41) / 2
t > 0, so:
t = (1 + √41) / 2
t ≈ 3.70
Answer:
the is D
Explanation:
An action-reaction force pair
Answer:
A) It takes the truck 8 s to catch the motorcycle.
B) The motorcycle has traveled 160 m in that time.
C) The velocity of the truck is 40 m/s at that time.
Explanation:
The equations of the position and velocity of an object moving in a straight line are as follows:
x = x0 +v0 · t + 1/2 · a · t²
v = v0 + a · t
Where:
x = position
x0 = initial position
v0 = initial velocity
t = time
a = acceleration
v = velocity at time t
(A) When the the truck catches the motorcycle, both have the same position. Notice that the motorcycle moves at constant speed so that a = 0:
x truck = x motorcycle
x0 +v0 · t + 1/2 · a · t² = x0 + v · t
Placing the origin of the frame of reference at the point where the truck starts, both have an initial position of 0. The initial velocity of the truck is 0. Then:
1/2 · a · t² = v · t
solving for t:
t = 2 v/a
t = 2 · 20 m/s/ 5 m/s²
t = 8 s
It takes the truck 8 s to catch the motorcycle.
(B) Using the equation of the position of the motorcycle, we can calculate the traveled distance in 8 s.
x = v · t
x = 20 m/s · 8 s
x = 160 m
(C) Now, we use the velocity equation at time 8 s.
v = v0 + a · t
v = 0 m/s + 5 m/s² · 8 s
v = 40 m/s
Answer:
The mass is essentially "how much stuff" is in an object. ... Weight: There is a gravitational interaction between objects that have mass. If you consider an object interacting with the Earth, this force is called the weight. The unit for weight is the Newton (same as for any other force).
Explanation:
Is this a book and most likely because the were cute
