All categories

3 years ago

How much force is needed to stop a 90-kg soccer player if he decelerates at 15 m/s²? A. 6 N B. 15 N C. 135 N D. 1350 N

Physics

2 answers:

Mariana [72]3 years ago

5 0

The answer is: D. 1350 N

Finger [1]3 years ago

3 0

The answer is 1350 N

You might be interested in

What category of the electromagnetic spectrum has a wavepength of 108m

vodomira [7]

Answer: Radio Waves

Explanation:

8 0

3 years ago

21) A youngster having a mass of 50.0 kg steps off a 1.00 m high platform. If she keeps her legs fairly rigid and comes to rest

zlopas [31]

Answer:

-22,150 N

Explanation:

When the youngster jumps off the platform, during the fall her initial potential energy is converted into kinetic energy, according to the law of conservation of energy. Therefore, we can write:

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

where the term on the left is the potential energy while the term on the right is the kinetic energy, and where

m = 50.0 kg is the mass of the youngster

$g=9.8 m/s^2$ is the acceleration due to gravity

h = 1.00 m is the heigth of the platform

u is the speed of the youngster as she reaches the floor

Solving for u,

$u=\sqrt{2gh}=\sqrt{2(9.8)(1.00)}=4.43 m/s$

Then, when the youngster hits the floor, the force exerted on her during the deceleration is given by:

$F=\frac{\Delta p}{\Delta t}=\frac{m(v-u)}{\Delta t}$

where $\Delta p$ is her change in momentum, and where

m is the mass

v = 0 is the final velocity (she comes to a stop)

u = 4.43 m/s is the initial velocity

$\Delta t=10.0 ms =0.010 s$ is the duration of the collision

Substituting,

$F=\frac{(50.0)(0-4.43)}{0.010}=-22150 N$

And the negative sign means the direction of the force is opposite to the motion (so, upward).

6 0

3 years ago

Which substance has the highest density at room temperature?

12345 [234]

I think phosphorus has the highest density at room temp.

6 0

3 years ago

About where is our solar system located within the milky way galaxy?

sashaice [31]

Solar system is nested nearly 2/3 of the way from the center of the galaxy to the outskirt of the galactic disc.

6 0

3 years ago

A particle with a charge of -4.0 μC and a mass of 3.2 x 10-6 kg is released from rest at point A and accelerates toward point B,

Assoli18 [71]

Answer:

$V_B-V_A=-20736-0=-20736volt$

Explanation:

We have given charge on the particle $q=-4\mu C=-4\times 10^{-6}C$

Mass of the charge particle $m=3.2\times 10^{-6}kg$

From energy of conservation kinetic energy will be equal to potential energy

So at point A

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

At point a velocity is zero

So $\frac{1}{2}(3.2\times10^{-6} )0^2=-4\times 10^{-6}V_a$

$V_A=0volt$

At point B velocity will be 72 m/sec

So $\frac{1}{2}\times 3.2\times 10^{-6}72^2=-4\times 10^{-6}V_b$

$V_B=-20736volt$

So $V_B-V_A=-20736-0=-20736volt$

4 0

3 years ago