Answer: W = 0.3853 J, e = 0.052 m
Explanation: Given that,
K =285.0N/M , L = 0.230m , F = 15N , e = ?
F = Ke
15 = 285 × e
e = 15÷ 285
e =0.052 m
e + L = 0.052 + 0.230
= 0.282m ( spring new length )
Work needed to stretch the spring
W = 1/2ke2
W = 1/2 × 285 x 0.052 × 0.052
W = 0.3853 J
Answer:
A) hydrostatic force on top of cube = 882.9N
B) hydrostatic force on sides of cube = 0N
Explanation:
Detailed explanation and calculation is shown in the image below
Explanation:
After some time t the current does not passing through the circuit
=>so the back emf is zero
=>here the inductor opposes decay of the circuit
- Ldi/dt = Ri
di/dt = - R/Li
di/i = - R/Ldt
now we applying the integration on both sides
log i=-R/Lt+C
here t=0=>i=io
Log io=C
=>Log i=-R/L*t + Log io
logi-Log io=-R/L*t
Log[i/io]=-R/L*t
i/io=e^-Rt/L
i=ioe^-Rt/L
the option D is correct
Answer:
B.The force of friction between the block and surface will decrease.
Explanation:
The force of friction is given by
where is the coefficient of friction and is the normal force.
When the student pulls on the block with force at an angle , the normal force on the block becomes
and hence the frictional force becomes
.
Now, as we increase , increases which as a result decreases the normal force , which also means the frictional force decreases; Hence choice B stands true.
<em>P.S: Choice D is tempting but incorrect since the weight </em><em> is independent of the external forces on the block. </em>