Answer:
0J
Option: B
Explanation:
Work is done when something is moved by the force in the direction of the force. That is the force (e.g., the weight) and the direction the object moves must be aligned for work to be done. In this given condition, the direction is horizontal and the force is downward as its gravity force. That 90° between the two vectors.
The work function is W = m × g ×h × cosθ
Hence,
Work done = 7 × 9.8 × 1.5 × cos(90)
Work done = 0 (cos
= 0)
Work done = 0
Therefore work done is 0 J.
To develop this problem we will apply the concepts related to angular kinematic movement, related to linear kinematic movement. Linear velocity can be described in terms of angular velocity as shown below,
Here,
v = Lineal velocity
= Angular velocity
r = Radius
Our values are
Replacing to find the angular velocity we have,
Convert the units to RPM we have that
Therefore the angular speed of the wheels when the scooter is moving forward at 6.00 m/s is 955.41rpm
Answer:
2.1844 m/s
Explanation:
The principle of conservation of momentum can be applied here.
when two objects interact, the total momentum remains the same provided no external forces are acting.
Consider the whole system , gun and bullet. as an isolated system, so the net momentum is constant. In particular before firing the gun, the net momentum is zero. The conservation of momentum,
assume the bullet goes to right side and the gravitational acceleration =10 
so now the weight of the rifle=
this is a negative velocity to the right side. that means the rifle recoils to the left side
Answer:
Final Length = 30 cm
Explanation:
The relationship between the force applied on a string and its stretching length, within the elastic limit, is given by Hooke's Law:
F = kΔx
where,
F = Force applied
k = spring constant
Δx = change in length of spring
First, we find the spring constant of the spring. For this purpose, we have the following data:
F = 50 N
Δx = change in length = 25 cm - 20 cm = 5 cm = 0.05 m
Therefore,
50 N = k(0.05 m)
k = 50 N/0.05 m
k = 1000 N/m
Now, we find the change in its length for F = 100 N:
100 N = (1000 N/m)Δx
Δx = (100 N)/(1000 N/m)
Δx = 0.1 m = 10 cm
but,
Δx = Final Length - Initial Length
10 cm = Final Length - 20 cm
Final Length = 10 cm + 20 cm
<u>Final Length = 30 cm</u>
