Sound waves travel faster through air than through solids. Please select the best answer from the choices provided T F

A bullet with a mass ????b=13.5 g is fired into a block of wood at velocity ????b=249. The block is attached to a spring that ha

larisa86 [58]

Answer:

$M = 0.436 kg$

Explanation:

As per energy conservation we can say that energy stored in the spring at the position of maximum compression must be equal to the kinetic energy of bullet and block system

so here we have

$\frac{1}{2}(m + M)v^2 = \frac{1}{2} kx^2$

here we know that

k = 205 N/m

x = 35 cm

$\frac{1}{2}(m + M)v^2 = \frac{1}{2}(205)(0.35)^2$

now by momentum conservation we know that

$mv_o = (m + M)v$

$v = \frac{m}{m + M} v_o$

now plug in all values in it

$v = \frac{0.0135}{0.0135 + M}(249)$

now from above equation

$\frac{1}{2}(0.0135 + M)( \frac{0.0135}{0.0135 + M}(249))^2 = 12.56$

$\frac{5.65}{0.0135 + M} = 12.56$

by solving above equation we have

$M = 0.436 kg$

3 0

4 years ago

A paintball’s mass is 0.0032kg. A typical paintball strikes a target moving at 85.3 m/s.

vekshin1

Answer:

A) If the paintball stops completely the magnitude of the change in the paintball’s momentum is $p=0.273kg*m/s$

B) If the paintball bounces off its target and afterward moves in the opposite direction with the same speed, the change in the paintball’s momentum is $p=0.546kg*m/s$

C) A paintball bouncing off your skin in the opposite direction with the same speed hurts more than a paintball exploding upon your skin because of the strength exerted is twice than if it explodes.

Explanation:

Hi

A) We use the formula of momentum $p=mv$ , so we have $p=0.0032kg*85.3m/s=0.273kg*m/s$

B) We use the same formula above, then due we have a change of direction at the same speed, therefore the change in the momentum is the double so

$p=2*0.0032kg*85.3m/s=0.546kg*m/s$ .

C) The average strength of the force an object exerts during impact is determined by the amount the object’s momentum changes. therefore

$F=\frac{\Delta p}{\Delta t}$ , as we don't have any data about the impact time but we know momentum is twice, time does no matter and strength is twice too.

4 0

4 years ago

Which type of foot PPE must you wear if electrical shock is ever a possibility with your job?

ira [324]

The appropriate PPE(personal protective equipment) to be worn for foot protection against electric shock is boots retrofitted with rubber soles. Rubber does not conduct electricity and so will safeguard against electric shocks.

Other personal protective equipment used in a lab or industry can include safety glasses, rubber gloves, protective clothing and masks and respirators. PPE goes hand in hand with personal behaviour, personal grooming and housekeeping.

7 0

3 years ago

A block slides along a frictionless surface and onto a slab with a rough surface. The slab has mass of 4 kg and the block has ma

maxonik [38]

Answer: the friction force on the small block at t equals 1 second is 2N

Explanation:

Given the data in the question;

from the slope in the graph provided, we will get the acceleration of the slab

At t = 1 seconds

Slope = acceleration = ( 1 - 0) / ( 2 - 0 ) = 1/2 = 0.5 m/s²

Force = ma = 4 × 0.5 = 2 N

so by Newton's third law

Force on block will be same which is 2N

Therefore the friction force on the small block at t equals 1 second is 2N

3 0

3 years ago

What is paleomagnetism how has it been used to understand plate tectonics?

Nonamiya [84]

<span>Plate tectonics is the theory that the earth's crust is broken up into plates that float on top of a hotter and more fluid layer below. Evidence to support this theory has been uncovered through the study of the earth's past magnetic field, known as paleomagnetism.</span>

8 0

4 years ago