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4 years ago

An object is 45 m above the ground when it is dropped. How fast is the object going just before it hits the ground?

1 answer:

3 0

This is a kinematics question.
$v^{2} = v_{0} ^{2} + 2g(y - y_{0}) \\ 
v^{2} = 0 + 2(-9.8)(0 - 45) \\ 
v^{2} = 882 \\ v = \sqrt{882} = 29.7 m/s$

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Why are fuse wires not provided in an electric circute containing an electric cell

Basile [38]

Hey there,

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4 years ago

How many Gigameters in 1600 meters

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3 years ago

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A student uses a spring with a spring constant of 130 N/m in his projectile apparatus. When 56 J of

Triss [41]

Explanation:

$potentional \: energy \: = \frac{1}{2} k {x}^{2} \\ 56 = \frac{1}{2} \times 130 \times {x}^{2} \\ {x}^{2} = \frac{56}{65} \\ x = \sqrt{ \frac{56}{65} } meter$

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3 years ago

Consult Multiple-Concept Example 11 for background material relating to this problem. A small rubber wheel on the shaft of a bic

Papessa [141]

Answer:

$Emf=24.4V$

Explanation:

From the question we are told that:

Angular speed $\omega=40*\omega'$

Radius $r=0.33m$

No. Turns $N=163$

Area $A= 3.23 * 10^{-3} m^2$

Magnetic field. $B=0.0948T$

Acceleration $a=0.60m/s^2$

Time $t=6.72s$

Generally the equation for momentum is mathematically given by

$\omega'=\omega_o+\frac[a}{r}t$

$\omega'=0+\frac{0.60}{0.33}*6.72$

$W=12.22rad/s^2$

Therefore

$\omega=Aw$

$\omega=12.22*40$

$\omega=488.7rads/s$

Generally the equation for Peak emf is mathematically given by

$Emf=NBA \omega$

$Emf=163*0.0948* 3.23 * 10^{-3} m^2*488.7rads/s$

$Emf=24.4V$

3 0

3 years ago

a disk initially at rest rotates with constant angular acceleration through an angel of 50 rad in 5 sec find the angular speed o

lisov135 [29]

Recall the formula,

∆θ = ω₀ t + 1/2 α t ²

where ∆θ = angular displacement, ω₀ = initial angular speed (which is zero because the disk starts at rest), α = angular acceleration, and t = time. Solve for the acceleration with the given information:

50 rad = 1/2 α (5 s)²

α = (100 rad) / (25 s²)

α = 4 rad/s²

Now find the angular speed ω after 3 s using the formula,

ω = ω₀ + α t

ω = (4 rad/s²) (3 s)

ω = 12 rad/s

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3 years ago