Question

a truck starts from rest and rolls down a hill with constant acceleration.it travels a distance of 400m in 20 sec find its acceleration.find the force acting on it if it's mass is 7 tonnes

Answer 1

Its your answer buddy

Answer 2

✤ᴀɴꜱᴡᴇʀ:-

• Acceleration of truck is 2m/s²
• Force acting on truck if it's mass is 7 tonnes is 14000 kgm/s²

✤ꜰᴏʀᴍᴜʟᴀ ᴛᴏ ʙᴇ ᴜꜱᴇᴅ :-

• s = ut + 1/2 at²

where,

s = Distance

u = initial velocity

t = time

a = acceleration

• F = ma

where,

F = force

m = mass

a = acceleration

✤ɢɪᴠᴇɴ

• Distance (s) = 400m
• Time (t) = 20s
• Mass (m) = 7 tones = 7000kg
• Initial velocity (u) = 0m/s

✤ꜱᴏʟᴜᴛɪᴏɴ :-

We know that,

Distance (s) = 400m

Time (t) = 20s

Mass (m) = 7 tones = 7000kg

Initial velocity (u) = 0m/s

$\bf \implies s = ut + 1/2 at²$

$\bf \implies 400 = 0 \times 20 + \frac{1}{2} \times a \times {20}^{2}$

$\bf \implies 400 = 0 + \frac{1}{2} a \times 400$

$\bf \implies 400 = \frac{1}{2} a \times 400$

$\bf \implies 400 = 200a$

$\bf \implies \frac{400}{200} = a$

$\bf \implies a = \frac{400}{200}$

$\bf \implies a = 2m/s²$

We know that,

Mass (m) = 7000

Acceleration (a) = 2m/s²

$\bf \implies F = ma$

$\bf \implies F = 7000 \times 2$

$\bf \implies F = 14000kgm/s²$

✏ᴀᴅᴅɪᴛɪᴏɴᴀʟʟʏ :-

Equations of motion are :-

• v = u + at
• s = ut + 1/2 at²
• 2as = v² - u²