Answer:
0.3m
Explanation:
Given parameters;
Elastic energy = 20J
Spring constant = 445N/m
Unknown
Final extension of the spring = ?
Solution:
The elastic potential energy of a stretched spring can be determined using the expression below;
EP = k e²
k is the spring constant
e is the extension
Insert the parameters and solve;
20 = x 445 x e²
multiply those sides by 2;
2(20) = 445e²
40 = 445e²
e² = = 0.09
e = √0.09 = 0.3m
The distance - time graph of the humming bird is missing, so i have attached it.
Answer:
Instantaneous velocity = 0.5 m/s
Explanation:
From the attached graph, at time t = 1 s, the corresponding distance is 0.5 m.
Instantaneous velocity is the velocity at that point.
Thus;
Instantaneous velocity = 0.5/1
Instantaneous velocity = 0.5 m/s
Answer:
work done is -2.8 × 10⁻⁶ J
Explanation:
Given the data in the question;
mass of the pendulum m = 6 kg
Length of core = 1.7 m
Now, case1, mass is pulled aside a small distance of 7.6 cm and released from rest. so let θ₁ be the angle made by mass with vertical axis.
so, θ₁ = ( 7.6 × 10⁻² m / 1.7 m ) = 0.045 rad
In case2, mass is pulled aside a small distance of 8 cm and released from rest. so let θ₁ be the angle made by mass with vertical axis.
so, θ₂ = ( 8 × 10⁻² m / 1.7 m ) = 0.047 rad.
Now, the required work done will be;
W = -cosθ
W = 6 × 9.8 × 1.7 × [ cos( 0.047 ) - cos( 0.045 ) ]
W = 6 × 9.8 × 1.7 × [ -2.8 × 10⁻⁸ ]
W = -2.8 × 10⁻⁶ J
Therefore, work done is -2.8 × 10⁻⁶ J