Answer:
80%
Explanation:
Efficiency of machine = work output/work input ×100 %
From question, work output = 20J
Work input = 25J.
Therefore efficiency = 20/25 × 100 %
Efficiency = 20×4 %
Efficiency = 80%
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Let
his and skateboard's combined mass is x
we know
F1=-F2
0.5kg*10m/s=-0.05m/s xkg
5=0.05x(minus cancel with the m/s as it represented the opposite direction of velocity and now there is no velocity in this equation.. so minus is avoidable. and the kgs cancel out)
x=10
so their combined mass is a 100 kg.. (I hope I didn't mess thing up for you)
14m/s
Explanation:
Given parameters:
Height of the ball = 10m
Unknown:
Velocity of fall or final velocity = ?
Solution:
We are going to use the appropriate equation of motion to solve this problem.
The object is falling with respect to gravity.
V² = U² + 2gH
where V is the final velocity
U is the initial velocity
g is the acceleration due to gravity 9.8m/s²
H is the height of fall
The initial velocity here is zero and
V² = 2 x 9.8 x 10 = 196
V = 14m/s
learn more:
Motion problems brainly.com/question/5248528
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Answer:
Explanation:
The amplitude is extraneous information for this question.
Period (T) is simply a measure of time (how long it takes to complete a full cycle).
The frequency (f), is the reciprocal (how many cycles it can complete per unit of time).
The frequency reported is 12Hz. Hz is a unit meaning "cycles per second"
Thus 12cycles = 1second.
To find the number of seconds per cycle, simply create the other unit fraction and simplify:

