Answer:
a) V ≈ 125 m/s; b) Δt = 13.24 s; c) ΔS ≈ 1450 m
Explanation:
a) We have just to calculate the vector resultant.
V² = 106² + 66.2²
V² = 15618.44
V ≈ 125 m/s
b) The time of flight is equal to the time to reach the maximum height summed to the time to reach the land.
In vertical:
V = V₀ + a * t
V = 66.2 - g * t
0 = 66.2 - 9.8 * t
t ≈ 6.76 s
So: Δt = 13.24 s
c) In horizontal:
V = ΔS / Δt
106 = ΔS / 13.52 ⇒ ΔS = 106 * 13.52
ΔS = 106 * 13.52
ΔS = 1433,12
ΔS ≈ 1450 m
Answer:
: Rocket weight on earth
: Rocket weight on moon
Explanation:
Conceptual analysis
Weight is the force with which a body is attracted due to the action of gravity and is calculated using the following formula:
W = m × g Formula (1)
W: weight
m: mass
g: acceleration due to gravity
The mass of a body on the moon is equal to the mass of a body on the earth
The acceleration due to gravity on a body is different on the moon and on the earth
Equivalences
1 slug = 14.59 kg
Known data
Problem development
To calculate the weight of the rocket on the moon and on earth we replace the data in formula (1):
: Rocket weight on earth
: Rocket weight on moon
Answer:
Kelly's weight would be 688.47 Newtons.
Explanation:
1 Kilogram would be 9.81 Newtons.
Answer:
0.75
Explanation:
Since the static frictional force is the maximum force applied just before sliding, our frictional force, F is 300 N.
Since F = μN where μ = coefficient of static friction and N = normal force = 400 N (which is the downward force applied against the surface).
So, μ = F/N
= 300 N/400 N
= 3/4
= 0.75
So, the coefficient of static friction μ = 0.75
I. Positive acceleration increases velocity. Negative acceleration decreases velocity. runner A sped up until the finish line and then slowed to a stop.
ii. Zero a acceleration implies a constant, unchanging velocity not a zero velocity. runner B achieved some velocity prior to 8s and is moving and must slow down to reach a stop.
iii. None. No aspects of this reasoning are correct. Everything she says is wrong. See iv for what/why.
iv. The sign on acceleration denotes the direction of *change in velocity* not change in direction. The sign on velocity can denote change in direction but only “forward” or “reverse” along a particular path. Cardinal direction is not indicated, generally, by the sign on velocity. It may correspond to North/South situationally but it is not an built-in feature of velocity and its sign. For example, if you are traveling with positive velocity and turn left to continue your journey you still have a positive velocity in the new direction. In fact, if you turn left again, traveling in the opposite direction as the one you started with your velocity would still be positive… in the new direction. The velocity relative to original direction could be said to be negative but that would be a confusing way to describe a journey. Maybe if you stopped the vehicle and moved in reverse, you could meaningfully say velocity was negative.
