All categories

3 years ago

A bungee jumper of mass m = 65 kg jumps from a bridge.

Physics

1 answer:

yawa3891 [41]3 years ago

3 0

To solve the problem it is necessary to apply energy conservation.

By definition we know that kinetic energy is equal to potential energy, therefore

PE = KE

$mgh = \frac{1}{2}mv^2$

Where,

m = mass

g = gravitaty constat

v = velocity

h = height

Re-arrange to find h,

$h=\frac{v^2}{2g}$

Replacing with our values

$h=\frac{26^2}{2*9.8}$

$h = 34.498\approx 34.5m$

Therefore the correct answer is C.

You might be interested in

How does Newtons second law of motion relate to Track and field (running sport)?

ANEK [815]

Newton's second law also helps to explain what happens every time an athlete lands during running. When the foot hits the track, it will decelerate to a stop before leaving the track again. The faster the deceleration, the greater the force of impact on the foot.

3 0

2 years ago

A steel playground slide is 5.25 m long and is raised 2.75 m on one end. A 45.0 kg child slides down from the top starting at re

Temka [501]

Answer:

$F=32.24N$

Explanation:

From the question we are told that:

Height $h= 2.75 m$

Length $l = 5.25 m$

Mass $m=45kg$

Final speed $v_f=6.81$

Generally the equation for Potential Energy P.E is mathematically given by

$P.E=mgh$

Therefore

Initial potential energy

$P.E_1=45*9.8*2.75 \\\\P.E_1= 1212.75 J$

Generally the equation for Kinetic Energy K.E is mathematically given by

$K.E=0.5mv^2$

Therefore

Final kinetic energy

$K.E_2= 1/2*45*6.81*6.81 \\\\K.E_2= 1043.46J$

Generally the equation for Work_done is mathematically given by

$W=P.E_1-K.E_2\\\\W=169.3$

Therefore

$F=\frac{W}{d}\\\\F=\frac{169.3}{5.25}$

$F=32.24N$

8 0

3 years ago

At least how many objects with charged particles must exist for there to be an electric force?

dimulka [17.4K]

Answer:

derecha, izquierda, derecha, arriba

Explanation:

6 0

3 years ago

Read 2 more answers

A lab technician uses laser light with a wavelength of 650 nmnm to test a diffraction grating. When the grating is 42.0 cmcm fro

Bingel [31]

Answer:

221 lines per millimetre

Explanation:

We know that for a diffraction grating, dsinθ =mλ where d = spacing between grating, θ = angle to maximum, m = order of maximum and λ = wavelength of light.

Since the grating is 42.0 cm from the screen and its first order maximum (m = 1) is at 6.09 cm from the center of the pattern,

tanθ = 6.09 cm/42.0 cm = 0.145

From trig ratios, cot²θ + 1 = cosec²θ

cosecθ = √((1/tanθ)² + 1) = √((1/0.145)² + 1) = √48.562 = 6.969

sinθ = 1/cosecθ = 1/6.969 = 0.1435

Also, sinθ = mλ/d at the first-order maximum, m = 1. So

sinθ = (1)λ/d = λ/d

Equating both expressions we have

0.1435 = λ/d

d = λ/0.1435

Now, λ = 650 nm = 650 × 10⁻⁹ m

d = 650 × 10⁻⁹ m/0.1435

d = 4529.62 × 10⁻⁹ m per line

d = 4.52962 × 10⁻⁶ m per line

d = 0.00452962 × 10⁻³ m per line

d = 0.00452962 mm per line

Since d = width of grating/number of lines of grating

Then number of lines per millimetre = 1/grating spacing

= 1/0.00452962

= 220.77 lines per millimetre

≅ 221 lines per millimetre since we can only have a whole number of lines.

6 0

3 years ago

The the temperature of the solvent, the more quickly the solute will dissolve.

steposvetlana [31]

Since temperature and kinetic energy of molecules are proportional, the more we increase the temperature of the solvent, the faster the solute will dissolve.

This increase of kinetic energy allows the solvent molecules to more effective break apart the solvent molecules that are held together by intermolecular forces.

5 0

3 years ago

Read 2 more answers