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3 years ago

Show your working please

Physics

1 answer:

saw5 [17]3 years ago

3 0

Explanation:

There's not enough information in the problem to solve it. We need to know either the initial speed of the lorry, or the time it takes to stop.

For example, if we assume the initial speed of the lorry is 25 m/s, then we can find the rate of deceleration:

v² = v₀² + 2aΔx

(0 m/s)² = (25 m/s)² + 2a (50 m)

a = -6.25 m/s²

We can then use Newton's second law to find the force:

F = ma

F = (7520 kg) (-6.25 m/s²)

F = -47000 N

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The system consists of a 20-lb disk A, 4-lb slender rod BC, and a 1-lb smooth collar C. If the disk rolls without slipping, dete

dlinn [17]

Answer:

The velocity of the collar will be 3.076 ft/s

Explanation:

Given data

weight of the disk, Wa = 20lb

weight of rod BC, Wbc = 4lb

weight of collar, Wc = 1lb

Considering the equation of equilibrium

Vb = 1.5Wbc

Wa = 1.875 Wbc

to calculate the velocity of the collar using energy conservation equation

T1 + V1 = T2 + V2

$0+4(1.5 \sin 45)+2(3 \sin 45)=\frac{1}{2}\left(\frac{1}{2}\left(\frac{20}{32.2}\right)(0.8)\right)$

=> $(1.875 W b c)+\frac{1}{2}\left(\frac{20}{32.2}\right)(1.5 W b c)+\frac{1}{2}\left(\frac{20}{32.2}\right)$

=> $(1.5 W b c) \frac{1}{2}\left\{\frac{1}{12}\left(\frac{4}{32.2}\right)(3)\right\}+\frac{1}{2}\left(\frac{1}{32.2}\right)$

=> $(2.598 W b c)+4(1.5 \sin 0)+2(3 \sin 0)$

Wbc = 1.18rad/sec

i.e.

$V _c=2.598 \times 1.18$

= 3.076 ft/ s

5 0

3 years ago

The acceleration of gravity on Earth is approximately 10 m/s2 (more precisely, 9.8 m/s2). If you drop a rock from a tall buildin

mars1129 [50]

Answer:

30 m/s

Explanation:

Velocity is $v_{final}=v_{initial}+at$ since we know that the initial velocity is 0, and the acceleration is $9.8 \frac{m}{s^2} \approx 10 \frac{m}{s^2}$ then we also know that time is 3 seconds it follows that: $v_{final}=v_{initial}+at=0+10\frac{m}{s^2}*3s=30\frac{m}{s}$

8 0

4 years ago

Plz help to answer the sheet above thanks

AysviL [449]

Answer:

(B) sound/kinetic

(E) Gravitational/kinetic

(F) mechanical/sound

Explanation:

(B) the useful energy transfer is sound but a by product of that is kinetic or mechanical energy because of the vibrations needed to make sound

(E) the useful energy transfer is Gravitational potential but a by product of that is kinetic or mechanical energy

(F) the useful energy transfer is kinetic or mechanical energy but the byproduct is noise and occasionally heat

6 0

3 years ago

In a police ballistics test, 2.00-g bullet traveling at 700 m/s suddenly hits and becomes embedded in a stationary 5.00-kg wood

aksik [14]

Answer:

Here we use the conservation of momentum theorem.

m stands for mass, and v stands for velocity. The numbers refer to the respective objects.

m1v1 + m2v2 = m1vf1 + m2vf2

Since the equation is perfectly inelastic, the final velocity of both masses is the same. Let’s account for this in our formula.

m1v1 + m2v2 = vf(m1 + m2)

<u>Let’s substitute in our givens.</u>

(0.002 kg)(700 m/s) + (5 kg)(0 m/s) = vf(0.002 kg + 5 kg)

I assume you are proficient in algebra I, so I will not include the steps to simplify this equation.

Note that I have considered the bullet’s velocity to be in the positive direction,

The answer is vf = 0.280 m/s

3 0

3 years ago

Which statement best describes the motion of an object that is being subjected to two forces of equal magnitude in opposite dire

Ludmilka [50]

The net force on the object is zero, so it has no acceleration. It moves in a straight line and at a constant speed (which may be zero).

8 0

4 years ago

Show your working please ​

Show your working please