Ask question

Ask question

All categories

23 days ago

9

In a common but dangerous prank, a chair is pulled away as a person is moving downward to sit on it, causing the victim to land

hard on the floor. Suppose the victim falls by 0.50 m, the mass that moves downward is 70 kg, and the collision on the floor lasts 0.082 s. What are the magnitudes of the (a) impulse and (b) average force acting on the victim from the floor during the collision?

1 answer:

kicyunya [3.2K]23 days ago

4 0

Answer:

a) Impulse |J|= 219.4 kgm/s

b) Force F = 2672 N

Explanation:

Given

Height of fall h = 0.50 m

Mass M = 70 kg

Duration of collision t = 0.082 s

Solution

The final velocity of the individual v is zero as they will come to a stop.

The initial velocity can be determined using the "law of conservation of energy".

Initial Kinetic energy = Final potential energy

$\frac{1}{2} mu^2=mgh\\\\u = \sqrt{2gh} \\\\u = \sqrt{2 \times 9.81 \times 0.50} \\\\u = 3.13 m/s$

a) Impulse

J = final momentum - initial momentum

$J = mv -mu\\\\J = 0 - (70 \times 3.13)\\\\J = -219.2 kgm/s$

Magnitude of impulse

$|J| = 219.1 kgm/s$

b) Force

$F = \frac{J}{t} \\\\F = \frac{219.1}{0.082} \\\\F = 2672 N$

You might be interested in

When you apply the torque equation ∑τ = 0 to an object in equilibrium, the axis about which torques are calculated:

Softa [3030]

Answer:

option D.

Explanation:

The correct choice is option D.

For an object in equilibrium, the torque measured at any point will be zero.

An object is deemed to be in equilibrium when the net moment acting on it equals zero.

If the object experiences a net moment not equal to zero, it will rotate and will not remain stable.

3 0

2 months ago

What upward gravitational force does a 5600kg elephant exert on the earth?

Keith_Richards [3271]

The force is calculated by multiplying mass and gravitational acceleration (F= mg). To find the solution, the mass of the elephant (5600 kg) is multiplied by gravity (9.8 m/s²). The result is 55,880 N, representing the upward gravitational force the elephant exerts on the Earth.

8 0

1 month ago

Read 2 more answers

Suppose that you measure the light of a star between 640 and 680 nm and you get a very strong peak around 650 nm. what can you s

kicyunya [3294]

The star is moving away from our planet. To elaborate on the Doppler shift: This phenomenon, related to the Doppler effect, is the variation in the perceived frequency or wavelength (color) of a wave when the source of the waves and the observer are in motion relative to one another. Consequently, it can be inferred that as an object recedes, it exhibits more redshift in its spectrum. For instance, when a star moves away, its spectral lines shift towards the red end of the spectrum, whereas if it approaches Earth, the spectral lines move towards blue. Given that the peak wavelength is roughly 650 nm—which is associated with red—it can be concluded that the star is indeed moving away from Earth.

3 0

19 days ago

Your annoying little brother is dropping rocks out of his bedroom window on the 2nd floor. You are on the ground floor and watch

serg [3582]

Answer:

Insufficient details provided; please clarify further.

5 0

2 months ago

Two friends, Burt and Ernie, are standing at opposite ends of a uniform log that is floating in a lake. The log is 3.2m long and

Softa [3030]

Answer:

x = 0.29 m

Explanation:

It is known that the total external force acting on the mass system equals ZERO,

so the center of mass of the entire system will stay stationary.

We find that

$m_1\Delta x_1 + m_2\Delta x_2 + m_3\Delta x_3 = 0$

Since Ernie approaches Burt's position, we have:

$33 x + 290 x + 32(-3.2 + x) = 0$

$355 x = 102.4$

therefore, we conclude that

$x = \frac{102.4}{355}$

$x = 0.29 m$

8 0

2 months ago