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3 years ago

In science, a force is a push or a pull. is it true or false ?

Engineering

1 answer:

AysviL [449]3 years ago

8 0

Answer:

true

Explanation:

because it is a external agency which Change or tends to change the state of rest or uniform motion in a straight line

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A strain gauge with a 4 mm gauge length gives a displacement reading of 1.5 um. Calculate the stress at the location of the stra

Art [367]

Answer:

1) 75Mpa

2) 1.125 MPa

Explanation:

given data:

gauge length = 4 mm

displacement $= 1.5\mu m = 1.5\times 10^{-3} m$

a) structural steel

Young modulus for steel is $200 GPa = 200\times 10^3 MPa$

we know that

$E =\frac{stress}{strain}$

$Stress = 200\times 10^3 \times \frac{1.5\times 10^{-3}}{4}$

= 75Mpa

b) PMMA

Young's modulus $= 3GPa = 3\times10^3 MPa$

$stress = 3\times \frac{1.5\times10^{-3}}{4}$

stress = 1.125 MPa

3 0

3 years ago

Two objects labeled K and L have equal mass but densities 0.95Do and Do, respectively. Each of these objects floats after being

Nonamiya [84]

Answer:

C. The buoyant forces are equal on the objects since they have equal mass.

Explanation:

Correct option (C) The buoyant forces are equal on the objects since they have equal mass. For floating objects, the buoyant force equals the weight of the objects. Since each object has the same weight, they must have the same buoyant force to counteract that weight and make them float.

4 0

3 years ago

An AM radio transmitter radiates 550 kW at a frequency of 740 kHz. How many photons per second does the emitter emit?

kifflom [539]

Answer:

1121.7 × 10³⁰ photons per second

Explanation:

Data provided in the question:

Power transmitted by the AM radio,P = 550 kW = 550 × 10³ W

Frequency of AM radio, f = 740 kHz = 740 × 10³ Hz

Now,

P = $\frac{NE}{t}$

here,

N is the number of photons

t is the time

E = energy = hf

h = plank's constant = 6.626 × 10⁻³⁴ m² kg / s

Thus,

P = $\frac{NE}{t}$ = $\frac{N\times(6.626\times10^{-34}\times740\times10^{3})}{1}$ [t = 1 s for per second]

550 × 10³ = $\frac{N\times(6.626\times10^{-34}\times740\times10^{3})}{1}$

550 = N × 4903.24 × 10⁻³⁴

N = 0.11217 × 10³⁴ = 1121.7 × 10³⁰ photons per second

7 0

3 years ago

Which physical quantity measures fraction of the input energy a machine actually concerts into output energy ?

Dvinal [7]

The answer is Kinetic Power.

4 0

3 years ago

Two concentric helical compression springs made of steel and having the same length when loaded and when unloaded are used to su

Andrews [41]

Answer:

see explaination for all the answers and full working.

Explanation:

deflection=8P*DN/Gd^4

G(for steel)=70Gpa=70*10^9N/m^2=70KN/mm^2

for outer spring,

deflection=8*3*50^3*5/(70*9^4)=32.66mm

for inner spring

deflection=8*3*30^3*10/(70*5^4)=148.11mm

max stress=k*8*P*C/(3.14*d^2)

for outer spring

c=50/9=5.55

k=(4c-1/4c-4)+.615/c=1.2768

max stress=1.2768*8*3*5.55/(3.14*9^2=.66KN.mm^2

for inner spring

c=6

k=1.2525

max stress=2.29KN/mm^2

6 0

4 years ago

Read 2 more answers