A time varying net force acts on a $8.0 k g$ block. Particle's displacement is given by $X = A t^{2} + B t + C$ $(A = 2 m / s^{2}, B = 6 m / s, C = 4 m)$ . Find work done on the block in first $4 s$ of motion.

1947

No worries! We‘ve got your back. Try BYJU‘S free classes today!

1857

No worries! We‘ve got your back. Try BYJU‘S free classes today!

1792

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

1869

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is C 1792
$X = 2 t^{2} + 6 t + 4$
$V = 4 t + 6$
at $t = 0, V = 6$
$t = 4, V =$ $4 \times 4 + 6 = 22$
$W = \frac{1}{2} m (V_{f}^{2} - V_{i}^{2})$
$= \frac{1}{2} .8 (22^{2} - 6^{2}) = 4 (484 - 36)$
$= 1792$

Suggest Corrections

Similar questions

Q. A time varying net force acts on a

8.0 k g

block. Particle's displacement is given by

X = A t^{2} + B t + C

(A = 2 m / s^{2}, B = 6 m / s, C = 4 m)

. Find work done on the block in first

4 s

of motion.

Q. Consider the situation as shown in figure. A constant force acting on the lower blocks produces an acceleration of

4 {m/s}^{2} .

The two blocks always move together. Find the work done by static friction on the upper block during displacement

2 m

of the system.

A block of mass 2.0 kg is pushed down an inclined place of inclination $37^{\circ}$ with a force of 20 N acting parallel to the incline. It is found that the block moves on the incline with an acceleration of 10 $m / s^{2}$ . If the block started from rest, find the work done (a) by the applied force in the first second, (b) by the weight of the block in the first second and (c) by the frictional force acting on the block in the first second. Take g= $10 m / s^{2}$ .

The net force on a body is varying with time as (2t + 3) N. Find the change in momentum of the body after 2 secs?

Q. Consider the situation as shown in figure. A constant force acting on the lower blocks produces an acceleration of

4 {m/s}^{2} .

The two blocks always move together. Find the work done by static friction on the upper block during displacement

2 m

of the system.

Join BYJU'S Learning Program

A time varying net force acts on a 8.0 kg block. Particle's displacement is given by X=At2+Bt+C (A=2 m/s2,B=6 m/s,C=4 m). Find work done on the block in first 4 s of motion.

The correct option is C 1792X=2t2+6t+4 V=4t+6 at t=0,V=6 t=4,V=4×4+6=22 W=12m(V2f−V2i) =12.8(222−62)=4(484−36) =1792

A time varying net force acts on a $8.0 k g$ block. Particle's displacement is given by $X = A t^{2} + B t + C$ $(A = 2 m / s^{2}, B = 6 m / s, C = 4 m)$ . Find work done on the block in first $4 s$ of motion.

The correct option is C 1792
$X = 2 t^{2} + 6 t + 4$
$V = 4 t + 6$
at $t = 0, V = 6$
$t = 4, V =$ $4 \times 4 + 6 = 22$
$W = \frac{1}{2} m (V_{f}^{2} - V_{i}^{2})$
$= \frac{1}{2} .8 (22^{2} - 6^{2}) = 4 (484 - 36)$
$= 1792$