Ask question

Ask question

All categories

3 years ago

11

A mechanic test driving a car that she has just given a tune-up accelerates from rest to 50.0 m/s in 9.8 s. How far (in meters)

does she travel in that time?

1 answer:

Stels [109]3 years ago

6 0

Answer:

245 m

Explanation:

v = at + v₀

50.0 m/s = a (9.8 s) + 0 m/s

a = 5.10 m/s²

x = x₀ + v₀ t + ½ at²

x = 0 m + (0 m/s) (9.8 s) + ½ (5.10 m/s²) (9.8 s)²

x = 245 m

You might be interested in

A firefighter with a weight of 707 N slides down a vertical pole with an acceleration of 2.79 m/s2, directed downward. (a) What

DedPeter [7]

Answer:

The vertical force acting on the firefighter = 908.27 N

Explanation:

Force: Force of a body is defined as the product of mass and its acceleration. The S.I unit of force is Newton (N)

The vertical force acting on the firefighter = Force due to the weight of the firefighter + force due to acceleration.

Ft = Fw - Fa

Where Ft = The vertical force acting on the firefighter, Fw = Force due to the weight of the firefighter, Fa = force due to acceleration.

Fw = mg

Making m the subject of formula in the equation above

m = Fw/g................... Equation 1

Where m = mass of the firefighter, g = acceleration due to gravity,

<em>Given: Fw = 707 N, </em>

<em> Constant: g = 9.8 m/s²</em>

Substituting these values into eqaution 1

m = 707/9.8

m = 72.14 kg.

But, Fa = ma

Where a = acceleration of the firefighter.

<em>Given: a = 2.79 m/s², </em>

<em>And m = 72.14 kg</em>

Fa = 72.14 × 2.79

Fa = 201.27 N

Therefore, Ft = 707 + 201.27 = 908.27 N

Ft = 908.27 N

The vertical force acting on the firefighter = 908.27 N

7 0

3 years ago

Someone is trying to balance a (110cm) plank with certain forces.

Mashutka [201]

Answer:

a. i. 30 Nm ii. This moment is a clockwise positive moment.

b. i. 15 Nm ii, This moment is a counter-clockwise negative moment.

c. i. The plank will not balance. ii. The plank would tip up.

d. 150 N

Explanation:

a) Calculate the moment of the 60N force (about O), then name its type.

i. Calculate the moment of the 60N force (about O)

Since moment = Force × perpendicular distance from point of moment ,

M = Fd

Since F = 60 N and d = 50 cm = 0.5 m

M = 60 N × 0.5 m = 30 Nm

ii. Then name its type.

This moment is a clockwise positive moment.

b) Calculate the moment of the 30N force (about O), then name its type.

i. Calculate the moment of the 30N force (about O),

Since moment = Force × perpendicular distance from point of moment ,

M' = F'd'

Since F' = 30 N and d' = 50 cm = 0.5 m

M' = 30 N × 0.5 m = 15 Nm

ii. Then name its type.

This moment is a counter-clockwise negative moment.

c) Will the plank balance? If not, which way will it tip?

i. Will the plank balance?

The plank will balance if the net moment on it is zero

So net moment, M' = positive moment - negative moment = M - M' = 30 Nm - 15 Nm = 15 Nm

Since the net moment on the plank is M" = 15 Nm ≠ 0,<u>the plank will not balance.</u>

ii Which way will it tip?

The plank would tip in the direction of the greater moment since the net moment is positive. <u>This moment tilts the plank in a clockwise direction, so the plank would tip up.</u>

d) What extra force would be needed at (B) to balance the plank?

The extra force must balance the net moment,

So M" = F"d" where F" = force and d" = distance of force from O = 10 cm = 0.10 m

F" = M"/d"

= 15 Nm/0.10 m

= 150 N

4 0

2 years ago

The process of digestion breaks down proteins into smaller molecules that are used to rebuild other proteins. During digestion,

Len [333]

The process of digestion breaks down proteins into smaller molecules that are used to rebuild other proteins. During digestion, proteins undergo chemical changes.

<u>Option: D</u>

<u>Explanation:</u>

Proteins are broken down into amino acids considered the foundational element. When issued, these tiny molecules can then be consumed into the bloodstream via the gut wall. An enzyme is a protein which can regulate biochemical response rate. An enzyme integrates a water molecule around the bond in enzymatic hydrolysis processes which allows it to split.

The bonds which hold together the amino acids are recognized as peptide bonds. A hydrolysis process comparable to that included in splitting up carbohydrates is required to break the peptide bonds within a protein. Enzymes identified as proteases are required for the protein to disintegrate.

7 0

3 years ago

Why are Watson’s experiments considered controversial?

iris [78.8K]

D, it is considered unethical today

4 0

3 years ago

Read 2 more answers

Two coils close to each other have a mutual inductance of 32 mH. If the current in one coil decays according to I=I0e−αt, where

fiasKO [112]

The emf induced in the second coil is given by:

V = -M(di/dt)

V = emf, M = mutual indutance, di/dt = change of current in the first coil over time

The current in the first coil is given by:

i = i₀ $e^{-at}$

i₀ = 5.0A, a = 2.0×10³s⁻¹

i = 5.0e^(-2.0×10³t)

Calculate di/dt by differentiating i with respect to t.

di/dt = -1.0×10⁴e^(-2.0×10³t)

Calculate a general formula for V. Givens:

M = 32×10⁻³H, di/dt = -1.0×10⁴e^(-2.0×10³t)

Plug in and solve for V:

V = -32×10⁻³(-1.0×10⁴e^(-2.0×10³t))

V = 320e^(-2.0×10³t)

We want to find the induced emf right after the current starts to decay. Plug in t = 0s:

V = 320e^(-2.0×10³(0))

V = 320e^0

V = 320 volts

We want to find the induced emf at t = 1.0×10⁻³s:

V = 320e^(-2.0×10³(1.0×10⁻³))

V = 43 volts

3 0

3 years ago