Question

An object accelerates from 10 m / s to 30 m / s in 4.0 seconds.The accelerating force is 150 N. What is the mass of the object? * 2 points A 0.033 kg B 5.0 kg C 7.5 kg D 30 kg

Answer 1

Given ,

• Initial velocity (u) = 10 m/s
• Final velocity (v) = 30 m/s
• Time (t) = 4 sec
• Force (f) = 150 N

As we know that , the first equation of motion is given by

$\star \: \: \sf v = u+ at$

Substitute the known values , we get

$\sf \Rightarrow 30 = 10 + a × 4 \\ \\ \sf \Rightarrow</p><p>20 = a × 4 \\ \\ \sf \Rightarrow</p><p>a = 5 \: \: m/ {s}^{2}$

By Newton's second law of motion ,

$\star \: \: \sf Force \: (f) = ma$

Thus ,

$\sf \Rightarrow 150 = m × 5</p><p> \\ \\ \sf \Rightarrow </p><p>m = 30 \: \: kg$

$\therefore \bold{ \sf \underline{The \: mass \: of \: the \: object \: is \: 30 \: \: kg }}$

Answer 2

$\rule{200}2$

$\huge\bold{\mathtt{QUESTION}}$

➡ An object accelerates from 10 m/s to 30 m/s in 4.0 seconds.The accelerating force is 150 N. What is the mass of the object?

$\rule{200}2$

$\huge\bold{\mathtt{SOLUTION}}$

↪INITIAL VELOCITY = 10 m/s

↪FINAL VELOCITY = 30 m/s

↪TIME = 4 seconds

↪FORCE = 150 N

✳ We have to find mass of the body !

→ For this first we need to find the acceleration of the body .

⚡ Formula used → v = u + at

▶ 30 = 10 + a(4)

▶30 - 10 = 4a

▶20 = 4a

▶a = $\sf \dfrac{20}{4}$

▶a = $\sf 5\: {m}^{2}$

⚡ Formula used → F = ma

▶150 = m(5)

▶m = $\sf \dfrac{150}{5}$

▶m = 30 kg

$\large{\boxed{\mathtt{Mass\:=\:30\:kg}}}$

$\rule{200}2$