A net force acting on an object causes the object to accelerate.
That much is totally true.
The direction of the acceleration is the direction of the net force.
Answer:
the initial force exerted on the rocket is 900 N
Explanation:
The computation of the initial force exterted on the rocket is shown below:
Force exerter = Rate of change of momentum
= 300 m/s × 3kg/s
= 900 N
hence, the initial force exerted on the rocket is 900 N
we simply multiplied the rate with its speed so that the force could come
Answer:
In 2.748 sec the mailbag reached the ground
Explanation:
We have given height from the ground
At t =2.25 sec helicopter releases a small mailbag so at t = 2.25 sec height from the ground
When the mail box is drooped its initial velocity would zero so u = 0 m/sec
Acceleration due to gravity
According to third law of motion
t = 2.748 sec
Answer:
(a) 1.64 rad/s²
(b) 39.94 rad
Explanation:
(a) From the question,
α = a/r................ Equation 1
Where a = linear acceleration if the motorcycle wheel, r = radius of the wheel, α = angular velocity of the wheel.
But,
a = (v-u)/t.............. Equation 2
Given: v = 1.4 m/s, u = 7.8 m/s, t = 5.8 s
Substitute into equation 2.
a = (1.4-7.8)/5.8
a = -1.1 m/s².
Note: The negative sign shows that the motorcycle is decelerating
Also given: r = 0.67 m.
Substitute into equation 1
α = 1.1/0.67
α = 1.64 rad/s²
(b)
Θ = s/r................... Equation 3
Where s = linear displacement, Θ = angular displacement.
But,
s = (v²-u²)/2a.......... Equation 2
s = (1.4²-7.8²)/[2×(-1.1)]
s = -58.88/-2.2
s = 26.76 m.
therefore,
Θ = 26.76/0.67
Θ = 39.94 rad.
1) At the moment of being at the top, the piston will not only tend to push the penny up but will also descend at a faster rate at which the penny can reach in 'free fall', in that short distance. Therefore, at the highest point, the penny will lose contact with the piston. Therefore the correct answer is C.
2) To solve this problem we will apply the equations related to the simple harmonic movement, hence we have that the acceleration can be defined as
Where,
a = Acceleration
A = Amplitude
= Angular velocity
From a reference system in which the downward acceleration is negative due to the force of gravity we will have to
From the definition of frequency and angular velocity we have to
Therefore the maximum frequency for which the penny just barely remains in place for the full cycle is 2.5Hz